lesson objectives students will be able to · lesson objectives students will be able to ... what...

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HONORS PHYSICS Linear Momentum LESSON OBJECTIVES Students will be able to... understand that forces can act over time (impulse) resulting in changes in momentum identify characteristics of motion with respect to momentum in a collision distinguish between elastic and inelastic collisions state the Law of Conservation of Momentum SKILLS Students will be able to... use appropriate metric units for given measurements use steps for solving physics problems solve problems using mass, velocity, momentum and conservation of momentum for inelastic collisions conduct experiments relating to momentum collect and display experiment data develop models of inelastic collisions VOCABULARY Newton’s Third Law momentum impulse law of conservation of momentum collision Impulse-Momentum theorem perfectly Inelastic collision HOMEWORK The Impulse-Momentum Change Theorem #1: Momentum, reading and homework #2: Momentum and Impulse Connection, reading and homework #3: Real-World Applications, reading The Law of Momentum Conservation #4: The Law of Action-Reaction (Revisited), reading and homework #5: Momentum Conservation Principle, reading #6: Isolated Systems, reading #7: Using Equations as a "Recipe", reading and homework 1, homework 2 #8: Using Equations as a Guide, reading and homework 1 #9: Momentum Conservation in Explosions, reading

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HONORS PHYSICS Linear Momentum

LESSON OBJECTIVES Students will be able to

understand that forces can act over time (impulse) resulting in changes in momentum identify characteristics of motion with respect to momentum in a collision distinguish between elastic and inelastic collisions state the Law of Conservation of Momentum

SKILLS Students will be able to

use appropriate metric units for given measurements use steps for solving physics problems solve problems using mass velocity momentum and conservation of momentum for inelastic

collisions conduct experiments relating to momentum collect and display experiment data develop models of inelastic collisions

VOCABULARY

Newtonrsquos Third Law

momentum

impulse

law of conservation of momentum

collision

Impulse-Momentum theorem

perfectly Inelastic collision

HOMEWORK The Impulse-Momentum Change Theorem

1 Momentum reading and homework 2 Momentum and Impulse Connection reading and homework 3 Real-World Applications reading

The Law of Momentum Conservation

4 The Law of Action-Reaction (Revisited) reading and homework 5 Momentum Conservation Principle reading 6 Isolated Systems reading

7 Using Equations as a Recipe reading and homework 1 homework 2 8 Using Equations as a Guide reading and homework 1 9 Momentum Conservation in Explosions reading

CONTENT OUTLINE

I The Impulse-Momentum Change Theorem A Momentum

a Defined b Calculating

B Impulse a Defined b Calculating

C Relation between impulse and momentum

II The Law of Conservation of Momentum A Connection to Newtonrsquos Third Law B Momentum Conservation Principle C Isolated Systems

a Collision and Impulse Problems b Perfectly inelastic collisions in one dimension

Chapter Questions 1 What is formula for momentum What is the unit of momentum

2 What is the difference between momentum and mass

3 Which has greater mass a bowling ball at rest or a rolling basketball Which has greater momentum

4 Is linear momentum conserved when two objects collide and stick together Is kinetic energy conserved

5 Why when you release an inflated but untied balloon does it fly across the room

6 How can a rocket change direction when it is far out of space and is essentially in a vacuum

7 A boy stands in the middle of a perfectly smooth frictionless frozen lake How can he set himself in motion

8 When rain falls from the sky what happens to its momentum as it hits the ground

9 What is impulse What is the unit of impulse

10 What is the difference between impulse and momentum How does impulse relate to momentum

11 When a glass falls will the impulse be greater if it lands on a plush carpet than if it lands on a hard floor

12 When a small car meshes with a large truck in a head-on collision which of these two experiences greater change in momentum

Chapter Problems Momentum of a Single Object

13 What is the momentum of a 3000 kg truck traveling at 25 ms

14 A 1500 kg ferryboat has a momentum of 25000 kgmiddotms What is the speed of the ferryboat

15 A car travels at a constant speed of 24 ms and has a momentum of 28800 kgmiddotms What is the

mass of the car

16 An 8 kg bowling ball rolls at a constant speed of 3 ms What is the momentum of the ball

17 A bicyclist travels at a constant speed of 7 ms What is the total mass of the bicycle and the boy when the total momentum is 490 kgmiddotms

18 When a 45 kg cannon ball leaves a barrel it has a momentum of 14000 kgmiddotms What is the speed of the ball at the end of the barrel

19 A 45 kg woman runs at a speed of 56 ms What is her momentum

20 A certain bowling ball rolls at a constant speed of 5 ms If the momentum of the ball is 425

kgmiddotms what is its mass

21 What is the speed of a 025 kg arrow with a momentum of 8 kgms

22 A 1500 kg car travels 400 m in 12 s What is its momentum

23 An electron has a mass of 91x10-31 kg What is its momentum if it is travelling at a speed of 35x106 ms

24 A 3 kg stone is dropped from a height of 4 m What is its momentum as it strikes the ground

Momentum of a System of Objects

25 Determine the momentum of a system that consists of two objects One object m1 has a mass

of 6 kg and a velocity of 13 ms towards the east and a second object m2 has a mass of 14 kg and a velocity of 7 ms in that same direction

26 Determine the momentum of a system that consists of two objects One object m1 has a mass of 6 kg and a velocity of 13 ms in the direction of the positive x-axis and a second object m2 has a mass of 14 kg and a velocity 7 ms in the direction of the negative x-axis

27 Determine the momentum of a system that consists of three objects One object m1 has a mass

of 7 kg and a velocity 23 ms towards the north a second object m2 has a mass of 9 kg and a velocity 7 ms towards the north and the third object m3 has a mass of 5 kg and a velocity of 42 ms towards the south

28 Determine the momentum of a system of the two objects One object m1 has a mass of 35 kg and a velocity of 37 ms towards the east and the second object m2 has a mass of 57 kg and a velocity of 43 ms towards the west

29 Determine the momentum of a system of the two objects One object m1 has a mass of 35 kg

and a velocity of 37 ms towards the north and the second object m2 has a mass of 57 kg and a velocity of 43 ms towards the south

30 Determine the momentum of a system that consists of three objects One object m1 has a mass

of 12 kg and a velocity 120 ms towards the east a second object m2 has a mass of 25 kg and a velocity 18 ms towards the west and the third object m3 has a mass of 1 kg and a velocity of 350 ms towards the east

Conservation of Momentum and Perfectly Inelastic Collisions

31 A 13500 kg railroad freight car travels on a level track at a speed of 45 ms It collides and

couples with a 25000 kg second car initially at rest and with brakes released What is the speed of the two cars after collision

32 A 40 kg girl skates at 35 ms on ice toward her 65 kg friend who is standing still with open arms As they collide and hold each other what is the speed of the couple

33 A 50 kg boy jumps off the front of a 15 kg skateboard moving forward Find the skateboardrsquos

velocity immediately after the boy jumps assuming that the skateboardrsquos initial velocity is 35 ms and the boyrsquos velocity when jumping off the front is 5 ms

34 A 001 kg bullet has a speed of 700 ms before it strikes a 095 kg wooden block that is stationary on a horizontal frictionless surface and remains inside of it What is the speed of the block after the bullet becomes embedded in it

35 A cannon ball with a mass of 100 kg flies in horizontal direction with a speed of 600 ms and strikes a railroad freight car filled with sand and initially at rest The total mass of the car and sand is 25600 kg Find the speed of the car after the ball becomes embedded it the sand

36 A 001 kg bullet is fired at a 05 kg block initially at rest The bullet moving with an initial speed of

400 ms emerges from the block with a speed of 300 ms What is the speed of the block after the collision

37 A 50 kg boy jumps off the back of a 15 kg skateboard moving forward Find the skateboardrsquos velocity immediately after the boy jumps assuming that the skateboardrsquos initial velocity is 35 ms and the boyrsquos velocity when jumping off the back is 5 ms

38 Two football players with mass 85 kg and 110 kg run directly toward each other with speeds 4

ms and 7 ms respectively If they grab each other as they collide what is the combined speed of the players just after the collision

39 An air track car with a mass of 055 kg and velocity of 58 ms to the right collides and couples with a 045 kg car moving to the left with a velocity of 39 ms What is the combined velocity of the cars just after the collision

40 An air track car with a mass of 025 kg and velocity of 34 ms to the right collides and couples with a 045 kg car moving to the left with a velocity of 39 ms What is the combined velocity of the cars just after the collision

41 A 15000 kg railroad car travels on a horizontal track with a constant speed of 12 ms A 6000 kg load is dropped onto the car What will be the carrsquos speed

42 A 55 kg skater at rest on a frictionless rink throws a 3 kg ball giving the ball a velocity of 8 ms What is the velocity of the skater immediately after

43 A 0015 kg bullet is fired at a 15 kg block initially at rest The bullet moving with an initial speed of 500 ms emerges from the block with a speed of 400 ms What is the speed of the block after the collision

44 A 40 kg surfer jumps off the front of a 20 kg surfboard moving forward Find the surfboardrsquos

velocity immediately after the girl jumps assuming that the surfboardrsquos initial velocity is 8 ms and the girlrsquos velocity when jumping off the front is 3 ms

45 A 40 kg surfer jumps off the back of a 20 kg surfboard moving forward Find the surfboardrsquos velocity immediately after the girl jumps assuming that the surfboardrsquos initial velocity is 8 ms and the girlrsquos velocity when jumping off the back is 3 ms

Elastic Collision Problems (without masses)

46 Two objects have an elastic collision Before the collision they approach one another with a velocity of 45 ms With what velocity will they be separating after the collision

47 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is +80 ms and of m2 is -40 ms After the collision the velocity of m1 is +50ms What is the velocity of m2

48 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is -120 ms and of m2 is +80 ms After the collision the velocity of m1 is +90ms What is the velocity of m2

49 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is +20 ms and of m2 is +90 ms After the collision what will be the velocity of m1

50 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is +20 ms and of m2 is +90 ms After the collision what will be the velocity of m2

51 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +10 ms and m2 is initially at rest After the collision what will be the velocity of m2

52 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +10 ms and m1 is initially at rest After the collision what will be the velocity of m2

53 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 10 mph and that of the baseball is 30 mph What is the speed of the ball leaving the bat

54 Two objects have an elastic collision Before the collision they approach one another with a velocity of 18 ms With what velocity will they be separating after the collision

55 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is +60 ms and of m2 is +40 ms After the collision the velocity of m1 is +50ms What is the velocity of m2

56 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is -50 ms and of m2 is +80 ms After the collision the velocity of m1 is +70ms What is the velocity of m2

57 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m1

58 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m2

59 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +20 ms and m2 is initially at rest After the collision what will be the velocity of m2

60 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +20 ms and m1 is initially at rest After the collision what will be the velocity of m2

61 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 25 mph and that of the baseball is 80 mph What is the speed of the ball leaving the bat

Elastic Collision Problems (with masses)

62 A ball of mass 034 kg moving with a speed of 27 ms to the right collides head on with a 024 kg ball at rest If the collision is elastic what is the speed and direction of each ball after the collision

63 An ice puck of mass 054 kg moving with a speed of 5ms to the right collides with a 028 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each ball after the collision

64 An air track car with a mass of 075 kg and velocity of 85 ms to the right collides elastically with a 065 kg car moving to the left with a velocity of 72 ms If the collision is elastic what is the speed and direction of each ball after the collision

65 An air track car with a mass of 085 kg and velocity of 34 ms to the right collides elastically with

a 095 kg car moving to the left with a velocity of 49 ms If the collision is elastic what is the speed and direction of each ball after the collision

66 A ball of mass 65 kg moving with a speed of 15 ms to the right collides head-on with a 35 kg ball which is at rest If the collision is elastic what is the speed and direction of each ball after the collision

67 An ice puck of mass 75 kg moving with a speed of 18 ms to the right collides with a 25 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each mass after the collision

Change of Momentum and Impulse

68 A 1200 kg car accelerates from 13 ms to 17 ms Find the change in momentum of the car

69 A small object with a momentum of 6 kgmiddotms to the west approaches head-on a large object

at rest The small object bounces straight back with a momentum of 5 kgmiddotms What is the change in the momentum of the small object What is the impulse exerted on the small ball What is the impulse exerted on the large object

70 A 003 kg golf ball is hit off the tee at a speed of 34 ms The golf club was in contact with the

ball for 0003 s What is the average force on ball by the golf club

71 A toy rocket achieves a velocity of 55 ms after 3 s when fired straight up If the average force exerted by the engine is 28 N what is the toyrsquos mass

72 A 15000 kg air jet accelerates from rest to 45 ms before it takes off What is the change in

momentum of the jet

73 A 0025 kg piece of clay is thrown into a wall and has a speed of 9 ms before it strikes the wall Find the change in momentum of the clay and the impulse exerted on the clay if it does not bounce from the wall

74 A small bouncy ball with a momentum of 8 kgmiddotms to the left approaches head-on a large door at rest The ball bounces straight back with a momentum of 6 kgmiddotms What is the change in the momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the door

75 A 007 kg tennis ball leaves a racket with a speed of 56 ms If the ball is in contact with the racket for 004 s what is the average force on the ball by the racket

76 A 0145 kg baseball reaches a speed of 36 ms when a bat strikes If the average force of 500 N was applied on the ball by the bat what is the impact time

77 A 017 kg hockey puck slows down from 54 ms to 35 ms when it slides on horizontal ice

surface Find the change in momentum of the puck

78 A 001 kg bullet is fired at 250 ms into a wooden block that is fixed The bullet emerges from the block with a speed of 120 ms What is the change in momentum of the bullet

79 A 005 kg tennis ball moves at a speed of 10 ms and is struck by a racket causing it to rebound in the opposite direction at a speed 16 ms What is the change in momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the racket

80 A 025 kg beach ball rolling at a speed of 7 ms collides with a heavy exercise ball at rest The beach ball bounces straight back with a speed of 4 ms That is the change in momentum of the beach ball What is the impulse exerted on the beach ball What is the impulse exerted on the exercise ball

81 A 016 kg hockey puck is moving on an icy horizontal surface with a speed of 5 ms A player

strikes the puck by a hockey stick after the impact the puck moves in opposite direction with a speed of 9 ms If the puck was in contact with the stick for 0005 s what is the average force on the puck by the stick

82 A constant force of 12 N acts for 5 s on a 5 kg object What is the change in objectrsquos velocity

83 A small object with a mass of 1 kg moves in a circular path with a constant speed of 5 ms

What is the change in momentum during frac12 of period one period

General Problems

84 The diagram above shows a ballistic pendulum A 10 g bullet is fired into the suspended 2 kg

block of wood and remains embedded inside it (a perfectly inelastic collision) After the impact of the bullet the block swings up to a maximum height h If the initial speed of the bullet was 35 ms

a What was the momentum of the bullet before the collision

b What was the kinetic energy of the bullet before the collision

c What was the velocity of the bullet-block system just after the collision

d What was the total kinetic energy of the bullet-block system after the collision

e What is the maximum possible potential energy of the bullet-block system when it reaches its maximum height

f What is the maximum possible height of the bullet-block system

A B

85 Two objects A and B with masses of 32 kg and 18 kg move on a frictionless horizontal surface Object A moves to the right at a constant speed of 51 ms while object B moves to the right at a constant speed 14 ms They collide and stick together (a perfectly inelastic collision)

a Determine the total momentum of the system (both objects) before the collision

b Determine the total kinetic energy of the system before the collision

c Find the speed of the two objects after the collision

d Find the total kinetic energy of the system after the collision

e Is the kinetic energy of the system conserved Explain

86 A small cube with a mass of 25 g slides along a frictionless horizontal surface at a constant speed of 18 ms until it collides with and sticks to a large wooden 35 kg block The large block is attached to the left end of a spring with a spring constant of 100 Nm as shown above

a What is the momentum of the cube before the collision

b What is the kinetic energy of the cube before the collision

c Find the speed of the combined cube and block system just after the collision

d Find the kinetic energy of the cube-block system just after the collision

e What is the maximum potential energy that can be stored in the spring due to this collision

f How far will the cube-block system move before it stops

87 A track consists of a frictionless incline plane which is a height of 05 m and a rough horizontal

section with a coefficient of kinetic friction 002 Block A whose mass is15 kg is released from the top of the incline plane slides down and collides instantaneously and inelastically with identical block B at the lowest point The two blocks move to the right through the rough section of the track until they stop

a Determine the initial potential energy of block A

b Determine the kinetic energy of block A at the lowest point just before the collision

c Find the speed of the two blocks just after the collision

d Find the kinetic energy of the two blocks just after the collision

e How far will the two blocks travel on the rough section of the track

f How much work will the friction force do during this time

88 A bullet of mass 001 kg is moving horizontally with a speed of 100 ms when it hits a block of mass 2 kg that is at rest on a horizontal surface with a coefficient of friction of 04 After the collision the bullet becomes embedded in the block

a What is the net momentum of the bullet-block system before the collision b What is the net momentum of the bullet-block system after the collision c What is the speed of the bullet-block system after the collision d Find the total energy of the bullet-block system before the collision e Find the total energy of the bullet-block system after the collision f Is the total energy conserved during the collision g Find the maximum traveled distance of the bullet-block after the collision

89 A 35 kg child moving at 5 ms jumps onto a 40 kg sled that is initially at rest on a horizontal ice surface with the coefficient of friction of 002

a Determine the total momentum of the child-sled system before the child jumps onto the sled

b Determine the total momentum of the child-sled system after the child jumps onto the sled

c Determine the velocity of the child-sled system after the child jumps onto the sled

d Determine the total energy of the child-sled system before the child jumps onto the sled

e Determine the total energy of the child-sled system after the child jumps onto the sled

f Determine the maximum horizontal distance that child-sled can go after the child jumps onto the sled

90 A 10 g piece of sticky clay moving horizontally with a speed of 12 ms strikes a pendulum bob and sticks to the bob The pendulum bob has a mass of 50 g and it is suspended from a 07 m string

a Find the momentum of the clay before the collision

b Find the momentum of the clay-bob system after the collision

c Find the velocity of the clay-bob system after the collision

d Find the kinetic energy of the clay-bob system after the collision

e Find the maximum height of the clay-bob system that they deflect after the collision

f What velocity should the clay have before the collision in order for the clay-bob system to complete one circle

91 As shown above a 035 kg cart is moving on a horizontal frictionless track with a speed of 5 ms

when it hits and sticks to a 16 kg cart initially at rest on the track The 16 kg cart is connected to one end of a massless spring with a spring constant 80 Nm

a Determine the momentum of the 035 kg cart before the collision b Determine the kinetic energy of the 035 kg cart before the collision c Determine the momentum of the carts after the collision d Determine the kinetic energy of the carts after the collision e Is the kinetic energy conserved during the collision Explain you reasoning f Determine the maximum displacement of the spring after the collision

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

CONTENT OUTLINE

I The Impulse-Momentum Change Theorem A Momentum

a Defined b Calculating

B Impulse a Defined b Calculating

C Relation between impulse and momentum

II The Law of Conservation of Momentum A Connection to Newtonrsquos Third Law B Momentum Conservation Principle C Isolated Systems

a Collision and Impulse Problems b Perfectly inelastic collisions in one dimension

Chapter Questions 1 What is formula for momentum What is the unit of momentum

2 What is the difference between momentum and mass

3 Which has greater mass a bowling ball at rest or a rolling basketball Which has greater momentum

4 Is linear momentum conserved when two objects collide and stick together Is kinetic energy conserved

5 Why when you release an inflated but untied balloon does it fly across the room

6 How can a rocket change direction when it is far out of space and is essentially in a vacuum

7 A boy stands in the middle of a perfectly smooth frictionless frozen lake How can he set himself in motion

8 When rain falls from the sky what happens to its momentum as it hits the ground

9 What is impulse What is the unit of impulse

10 What is the difference between impulse and momentum How does impulse relate to momentum

11 When a glass falls will the impulse be greater if it lands on a plush carpet than if it lands on a hard floor

12 When a small car meshes with a large truck in a head-on collision which of these two experiences greater change in momentum

Chapter Problems Momentum of a Single Object

13 What is the momentum of a 3000 kg truck traveling at 25 ms

14 A 1500 kg ferryboat has a momentum of 25000 kgmiddotms What is the speed of the ferryboat

15 A car travels at a constant speed of 24 ms and has a momentum of 28800 kgmiddotms What is the

mass of the car

16 An 8 kg bowling ball rolls at a constant speed of 3 ms What is the momentum of the ball

17 A bicyclist travels at a constant speed of 7 ms What is the total mass of the bicycle and the boy when the total momentum is 490 kgmiddotms

18 When a 45 kg cannon ball leaves a barrel it has a momentum of 14000 kgmiddotms What is the speed of the ball at the end of the barrel

19 A 45 kg woman runs at a speed of 56 ms What is her momentum

20 A certain bowling ball rolls at a constant speed of 5 ms If the momentum of the ball is 425

kgmiddotms what is its mass

21 What is the speed of a 025 kg arrow with a momentum of 8 kgms

22 A 1500 kg car travels 400 m in 12 s What is its momentum

23 An electron has a mass of 91x10-31 kg What is its momentum if it is travelling at a speed of 35x106 ms

24 A 3 kg stone is dropped from a height of 4 m What is its momentum as it strikes the ground

Momentum of a System of Objects

25 Determine the momentum of a system that consists of two objects One object m1 has a mass

of 6 kg and a velocity of 13 ms towards the east and a second object m2 has a mass of 14 kg and a velocity of 7 ms in that same direction

26 Determine the momentum of a system that consists of two objects One object m1 has a mass of 6 kg and a velocity of 13 ms in the direction of the positive x-axis and a second object m2 has a mass of 14 kg and a velocity 7 ms in the direction of the negative x-axis

27 Determine the momentum of a system that consists of three objects One object m1 has a mass

of 7 kg and a velocity 23 ms towards the north a second object m2 has a mass of 9 kg and a velocity 7 ms towards the north and the third object m3 has a mass of 5 kg and a velocity of 42 ms towards the south

28 Determine the momentum of a system of the two objects One object m1 has a mass of 35 kg and a velocity of 37 ms towards the east and the second object m2 has a mass of 57 kg and a velocity of 43 ms towards the west

29 Determine the momentum of a system of the two objects One object m1 has a mass of 35 kg

and a velocity of 37 ms towards the north and the second object m2 has a mass of 57 kg and a velocity of 43 ms towards the south

30 Determine the momentum of a system that consists of three objects One object m1 has a mass

of 12 kg and a velocity 120 ms towards the east a second object m2 has a mass of 25 kg and a velocity 18 ms towards the west and the third object m3 has a mass of 1 kg and a velocity of 350 ms towards the east

Conservation of Momentum and Perfectly Inelastic Collisions

31 A 13500 kg railroad freight car travels on a level track at a speed of 45 ms It collides and

couples with a 25000 kg second car initially at rest and with brakes released What is the speed of the two cars after collision

32 A 40 kg girl skates at 35 ms on ice toward her 65 kg friend who is standing still with open arms As they collide and hold each other what is the speed of the couple

33 A 50 kg boy jumps off the front of a 15 kg skateboard moving forward Find the skateboardrsquos

velocity immediately after the boy jumps assuming that the skateboardrsquos initial velocity is 35 ms and the boyrsquos velocity when jumping off the front is 5 ms

34 A 001 kg bullet has a speed of 700 ms before it strikes a 095 kg wooden block that is stationary on a horizontal frictionless surface and remains inside of it What is the speed of the block after the bullet becomes embedded in it

35 A cannon ball with a mass of 100 kg flies in horizontal direction with a speed of 600 ms and strikes a railroad freight car filled with sand and initially at rest The total mass of the car and sand is 25600 kg Find the speed of the car after the ball becomes embedded it the sand

36 A 001 kg bullet is fired at a 05 kg block initially at rest The bullet moving with an initial speed of

400 ms emerges from the block with a speed of 300 ms What is the speed of the block after the collision

37 A 50 kg boy jumps off the back of a 15 kg skateboard moving forward Find the skateboardrsquos velocity immediately after the boy jumps assuming that the skateboardrsquos initial velocity is 35 ms and the boyrsquos velocity when jumping off the back is 5 ms

38 Two football players with mass 85 kg and 110 kg run directly toward each other with speeds 4

ms and 7 ms respectively If they grab each other as they collide what is the combined speed of the players just after the collision

39 An air track car with a mass of 055 kg and velocity of 58 ms to the right collides and couples with a 045 kg car moving to the left with a velocity of 39 ms What is the combined velocity of the cars just after the collision

40 An air track car with a mass of 025 kg and velocity of 34 ms to the right collides and couples with a 045 kg car moving to the left with a velocity of 39 ms What is the combined velocity of the cars just after the collision

41 A 15000 kg railroad car travels on a horizontal track with a constant speed of 12 ms A 6000 kg load is dropped onto the car What will be the carrsquos speed

42 A 55 kg skater at rest on a frictionless rink throws a 3 kg ball giving the ball a velocity of 8 ms What is the velocity of the skater immediately after

43 A 0015 kg bullet is fired at a 15 kg block initially at rest The bullet moving with an initial speed of 500 ms emerges from the block with a speed of 400 ms What is the speed of the block after the collision

44 A 40 kg surfer jumps off the front of a 20 kg surfboard moving forward Find the surfboardrsquos

velocity immediately after the girl jumps assuming that the surfboardrsquos initial velocity is 8 ms and the girlrsquos velocity when jumping off the front is 3 ms

45 A 40 kg surfer jumps off the back of a 20 kg surfboard moving forward Find the surfboardrsquos velocity immediately after the girl jumps assuming that the surfboardrsquos initial velocity is 8 ms and the girlrsquos velocity when jumping off the back is 3 ms

Elastic Collision Problems (without masses)

46 Two objects have an elastic collision Before the collision they approach one another with a velocity of 45 ms With what velocity will they be separating after the collision

47 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is +80 ms and of m2 is -40 ms After the collision the velocity of m1 is +50ms What is the velocity of m2

48 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is -120 ms and of m2 is +80 ms After the collision the velocity of m1 is +90ms What is the velocity of m2

49 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is +20 ms and of m2 is +90 ms After the collision what will be the velocity of m1

50 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is +20 ms and of m2 is +90 ms After the collision what will be the velocity of m2

51 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +10 ms and m2 is initially at rest After the collision what will be the velocity of m2

52 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +10 ms and m1 is initially at rest After the collision what will be the velocity of m2

53 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 10 mph and that of the baseball is 30 mph What is the speed of the ball leaving the bat

54 Two objects have an elastic collision Before the collision they approach one another with a velocity of 18 ms With what velocity will they be separating after the collision

55 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is +60 ms and of m2 is +40 ms After the collision the velocity of m1 is +50ms What is the velocity of m2

56 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is -50 ms and of m2 is +80 ms After the collision the velocity of m1 is +70ms What is the velocity of m2

57 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m1

58 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m2

59 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +20 ms and m2 is initially at rest After the collision what will be the velocity of m2

60 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +20 ms and m1 is initially at rest After the collision what will be the velocity of m2

61 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 25 mph and that of the baseball is 80 mph What is the speed of the ball leaving the bat

Elastic Collision Problems (with masses)

62 A ball of mass 034 kg moving with a speed of 27 ms to the right collides head on with a 024 kg ball at rest If the collision is elastic what is the speed and direction of each ball after the collision

63 An ice puck of mass 054 kg moving with a speed of 5ms to the right collides with a 028 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each ball after the collision

64 An air track car with a mass of 075 kg and velocity of 85 ms to the right collides elastically with a 065 kg car moving to the left with a velocity of 72 ms If the collision is elastic what is the speed and direction of each ball after the collision

65 An air track car with a mass of 085 kg and velocity of 34 ms to the right collides elastically with

a 095 kg car moving to the left with a velocity of 49 ms If the collision is elastic what is the speed and direction of each ball after the collision

66 A ball of mass 65 kg moving with a speed of 15 ms to the right collides head-on with a 35 kg ball which is at rest If the collision is elastic what is the speed and direction of each ball after the collision

67 An ice puck of mass 75 kg moving with a speed of 18 ms to the right collides with a 25 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each mass after the collision

Change of Momentum and Impulse

68 A 1200 kg car accelerates from 13 ms to 17 ms Find the change in momentum of the car

69 A small object with a momentum of 6 kgmiddotms to the west approaches head-on a large object

at rest The small object bounces straight back with a momentum of 5 kgmiddotms What is the change in the momentum of the small object What is the impulse exerted on the small ball What is the impulse exerted on the large object

70 A 003 kg golf ball is hit off the tee at a speed of 34 ms The golf club was in contact with the

ball for 0003 s What is the average force on ball by the golf club

71 A toy rocket achieves a velocity of 55 ms after 3 s when fired straight up If the average force exerted by the engine is 28 N what is the toyrsquos mass

72 A 15000 kg air jet accelerates from rest to 45 ms before it takes off What is the change in

momentum of the jet

73 A 0025 kg piece of clay is thrown into a wall and has a speed of 9 ms before it strikes the wall Find the change in momentum of the clay and the impulse exerted on the clay if it does not bounce from the wall

74 A small bouncy ball with a momentum of 8 kgmiddotms to the left approaches head-on a large door at rest The ball bounces straight back with a momentum of 6 kgmiddotms What is the change in the momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the door

75 A 007 kg tennis ball leaves a racket with a speed of 56 ms If the ball is in contact with the racket for 004 s what is the average force on the ball by the racket

76 A 0145 kg baseball reaches a speed of 36 ms when a bat strikes If the average force of 500 N was applied on the ball by the bat what is the impact time

77 A 017 kg hockey puck slows down from 54 ms to 35 ms when it slides on horizontal ice

surface Find the change in momentum of the puck

78 A 001 kg bullet is fired at 250 ms into a wooden block that is fixed The bullet emerges from the block with a speed of 120 ms What is the change in momentum of the bullet

79 A 005 kg tennis ball moves at a speed of 10 ms and is struck by a racket causing it to rebound in the opposite direction at a speed 16 ms What is the change in momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the racket

80 A 025 kg beach ball rolling at a speed of 7 ms collides with a heavy exercise ball at rest The beach ball bounces straight back with a speed of 4 ms That is the change in momentum of the beach ball What is the impulse exerted on the beach ball What is the impulse exerted on the exercise ball

81 A 016 kg hockey puck is moving on an icy horizontal surface with a speed of 5 ms A player

strikes the puck by a hockey stick after the impact the puck moves in opposite direction with a speed of 9 ms If the puck was in contact with the stick for 0005 s what is the average force on the puck by the stick

82 A constant force of 12 N acts for 5 s on a 5 kg object What is the change in objectrsquos velocity

83 A small object with a mass of 1 kg moves in a circular path with a constant speed of 5 ms

What is the change in momentum during frac12 of period one period

General Problems

84 The diagram above shows a ballistic pendulum A 10 g bullet is fired into the suspended 2 kg

block of wood and remains embedded inside it (a perfectly inelastic collision) After the impact of the bullet the block swings up to a maximum height h If the initial speed of the bullet was 35 ms

a What was the momentum of the bullet before the collision

b What was the kinetic energy of the bullet before the collision

c What was the velocity of the bullet-block system just after the collision

d What was the total kinetic energy of the bullet-block system after the collision

e What is the maximum possible potential energy of the bullet-block system when it reaches its maximum height

f What is the maximum possible height of the bullet-block system

A B

85 Two objects A and B with masses of 32 kg and 18 kg move on a frictionless horizontal surface Object A moves to the right at a constant speed of 51 ms while object B moves to the right at a constant speed 14 ms They collide and stick together (a perfectly inelastic collision)

a Determine the total momentum of the system (both objects) before the collision

b Determine the total kinetic energy of the system before the collision

c Find the speed of the two objects after the collision

d Find the total kinetic energy of the system after the collision

e Is the kinetic energy of the system conserved Explain

86 A small cube with a mass of 25 g slides along a frictionless horizontal surface at a constant speed of 18 ms until it collides with and sticks to a large wooden 35 kg block The large block is attached to the left end of a spring with a spring constant of 100 Nm as shown above

a What is the momentum of the cube before the collision

b What is the kinetic energy of the cube before the collision

c Find the speed of the combined cube and block system just after the collision

d Find the kinetic energy of the cube-block system just after the collision

e What is the maximum potential energy that can be stored in the spring due to this collision

f How far will the cube-block system move before it stops

87 A track consists of a frictionless incline plane which is a height of 05 m and a rough horizontal

section with a coefficient of kinetic friction 002 Block A whose mass is15 kg is released from the top of the incline plane slides down and collides instantaneously and inelastically with identical block B at the lowest point The two blocks move to the right through the rough section of the track until they stop

a Determine the initial potential energy of block A

b Determine the kinetic energy of block A at the lowest point just before the collision

c Find the speed of the two blocks just after the collision

d Find the kinetic energy of the two blocks just after the collision

e How far will the two blocks travel on the rough section of the track

f How much work will the friction force do during this time

88 A bullet of mass 001 kg is moving horizontally with a speed of 100 ms when it hits a block of mass 2 kg that is at rest on a horizontal surface with a coefficient of friction of 04 After the collision the bullet becomes embedded in the block

a What is the net momentum of the bullet-block system before the collision b What is the net momentum of the bullet-block system after the collision c What is the speed of the bullet-block system after the collision d Find the total energy of the bullet-block system before the collision e Find the total energy of the bullet-block system after the collision f Is the total energy conserved during the collision g Find the maximum traveled distance of the bullet-block after the collision

89 A 35 kg child moving at 5 ms jumps onto a 40 kg sled that is initially at rest on a horizontal ice surface with the coefficient of friction of 002

a Determine the total momentum of the child-sled system before the child jumps onto the sled

b Determine the total momentum of the child-sled system after the child jumps onto the sled

c Determine the velocity of the child-sled system after the child jumps onto the sled

d Determine the total energy of the child-sled system before the child jumps onto the sled

e Determine the total energy of the child-sled system after the child jumps onto the sled

f Determine the maximum horizontal distance that child-sled can go after the child jumps onto the sled

90 A 10 g piece of sticky clay moving horizontally with a speed of 12 ms strikes a pendulum bob and sticks to the bob The pendulum bob has a mass of 50 g and it is suspended from a 07 m string

a Find the momentum of the clay before the collision

b Find the momentum of the clay-bob system after the collision

c Find the velocity of the clay-bob system after the collision

d Find the kinetic energy of the clay-bob system after the collision

e Find the maximum height of the clay-bob system that they deflect after the collision

f What velocity should the clay have before the collision in order for the clay-bob system to complete one circle

91 As shown above a 035 kg cart is moving on a horizontal frictionless track with a speed of 5 ms

when it hits and sticks to a 16 kg cart initially at rest on the track The 16 kg cart is connected to one end of a massless spring with a spring constant 80 Nm

a Determine the momentum of the 035 kg cart before the collision b Determine the kinetic energy of the 035 kg cart before the collision c Determine the momentum of the carts after the collision d Determine the kinetic energy of the carts after the collision e Is the kinetic energy conserved during the collision Explain you reasoning f Determine the maximum displacement of the spring after the collision

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

Chapter Questions 1 What is formula for momentum What is the unit of momentum

2 What is the difference between momentum and mass

3 Which has greater mass a bowling ball at rest or a rolling basketball Which has greater momentum

4 Is linear momentum conserved when two objects collide and stick together Is kinetic energy conserved

5 Why when you release an inflated but untied balloon does it fly across the room

6 How can a rocket change direction when it is far out of space and is essentially in a vacuum

7 A boy stands in the middle of a perfectly smooth frictionless frozen lake How can he set himself in motion

8 When rain falls from the sky what happens to its momentum as it hits the ground

9 What is impulse What is the unit of impulse

10 What is the difference between impulse and momentum How does impulse relate to momentum

11 When a glass falls will the impulse be greater if it lands on a plush carpet than if it lands on a hard floor

12 When a small car meshes with a large truck in a head-on collision which of these two experiences greater change in momentum

Chapter Problems Momentum of a Single Object

13 What is the momentum of a 3000 kg truck traveling at 25 ms

14 A 1500 kg ferryboat has a momentum of 25000 kgmiddotms What is the speed of the ferryboat

15 A car travels at a constant speed of 24 ms and has a momentum of 28800 kgmiddotms What is the

mass of the car

16 An 8 kg bowling ball rolls at a constant speed of 3 ms What is the momentum of the ball

17 A bicyclist travels at a constant speed of 7 ms What is the total mass of the bicycle and the boy when the total momentum is 490 kgmiddotms

18 When a 45 kg cannon ball leaves a barrel it has a momentum of 14000 kgmiddotms What is the speed of the ball at the end of the barrel

19 A 45 kg woman runs at a speed of 56 ms What is her momentum

20 A certain bowling ball rolls at a constant speed of 5 ms If the momentum of the ball is 425

kgmiddotms what is its mass

21 What is the speed of a 025 kg arrow with a momentum of 8 kgms

22 A 1500 kg car travels 400 m in 12 s What is its momentum

23 An electron has a mass of 91x10-31 kg What is its momentum if it is travelling at a speed of 35x106 ms

24 A 3 kg stone is dropped from a height of 4 m What is its momentum as it strikes the ground

Momentum of a System of Objects

25 Determine the momentum of a system that consists of two objects One object m1 has a mass

of 6 kg and a velocity of 13 ms towards the east and a second object m2 has a mass of 14 kg and a velocity of 7 ms in that same direction

26 Determine the momentum of a system that consists of two objects One object m1 has a mass of 6 kg and a velocity of 13 ms in the direction of the positive x-axis and a second object m2 has a mass of 14 kg and a velocity 7 ms in the direction of the negative x-axis

27 Determine the momentum of a system that consists of three objects One object m1 has a mass

of 7 kg and a velocity 23 ms towards the north a second object m2 has a mass of 9 kg and a velocity 7 ms towards the north and the third object m3 has a mass of 5 kg and a velocity of 42 ms towards the south

28 Determine the momentum of a system of the two objects One object m1 has a mass of 35 kg and a velocity of 37 ms towards the east and the second object m2 has a mass of 57 kg and a velocity of 43 ms towards the west

29 Determine the momentum of a system of the two objects One object m1 has a mass of 35 kg

and a velocity of 37 ms towards the north and the second object m2 has a mass of 57 kg and a velocity of 43 ms towards the south

30 Determine the momentum of a system that consists of three objects One object m1 has a mass

of 12 kg and a velocity 120 ms towards the east a second object m2 has a mass of 25 kg and a velocity 18 ms towards the west and the third object m3 has a mass of 1 kg and a velocity of 350 ms towards the east

Conservation of Momentum and Perfectly Inelastic Collisions

31 A 13500 kg railroad freight car travels on a level track at a speed of 45 ms It collides and

couples with a 25000 kg second car initially at rest and with brakes released What is the speed of the two cars after collision

32 A 40 kg girl skates at 35 ms on ice toward her 65 kg friend who is standing still with open arms As they collide and hold each other what is the speed of the couple

33 A 50 kg boy jumps off the front of a 15 kg skateboard moving forward Find the skateboardrsquos

velocity immediately after the boy jumps assuming that the skateboardrsquos initial velocity is 35 ms and the boyrsquos velocity when jumping off the front is 5 ms

34 A 001 kg bullet has a speed of 700 ms before it strikes a 095 kg wooden block that is stationary on a horizontal frictionless surface and remains inside of it What is the speed of the block after the bullet becomes embedded in it

35 A cannon ball with a mass of 100 kg flies in horizontal direction with a speed of 600 ms and strikes a railroad freight car filled with sand and initially at rest The total mass of the car and sand is 25600 kg Find the speed of the car after the ball becomes embedded it the sand

36 A 001 kg bullet is fired at a 05 kg block initially at rest The bullet moving with an initial speed of

400 ms emerges from the block with a speed of 300 ms What is the speed of the block after the collision

37 A 50 kg boy jumps off the back of a 15 kg skateboard moving forward Find the skateboardrsquos velocity immediately after the boy jumps assuming that the skateboardrsquos initial velocity is 35 ms and the boyrsquos velocity when jumping off the back is 5 ms

38 Two football players with mass 85 kg and 110 kg run directly toward each other with speeds 4

ms and 7 ms respectively If they grab each other as they collide what is the combined speed of the players just after the collision

39 An air track car with a mass of 055 kg and velocity of 58 ms to the right collides and couples with a 045 kg car moving to the left with a velocity of 39 ms What is the combined velocity of the cars just after the collision

40 An air track car with a mass of 025 kg and velocity of 34 ms to the right collides and couples with a 045 kg car moving to the left with a velocity of 39 ms What is the combined velocity of the cars just after the collision

41 A 15000 kg railroad car travels on a horizontal track with a constant speed of 12 ms A 6000 kg load is dropped onto the car What will be the carrsquos speed

42 A 55 kg skater at rest on a frictionless rink throws a 3 kg ball giving the ball a velocity of 8 ms What is the velocity of the skater immediately after

43 A 0015 kg bullet is fired at a 15 kg block initially at rest The bullet moving with an initial speed of 500 ms emerges from the block with a speed of 400 ms What is the speed of the block after the collision

44 A 40 kg surfer jumps off the front of a 20 kg surfboard moving forward Find the surfboardrsquos

velocity immediately after the girl jumps assuming that the surfboardrsquos initial velocity is 8 ms and the girlrsquos velocity when jumping off the front is 3 ms

45 A 40 kg surfer jumps off the back of a 20 kg surfboard moving forward Find the surfboardrsquos velocity immediately after the girl jumps assuming that the surfboardrsquos initial velocity is 8 ms and the girlrsquos velocity when jumping off the back is 3 ms

Elastic Collision Problems (without masses)

46 Two objects have an elastic collision Before the collision they approach one another with a velocity of 45 ms With what velocity will they be separating after the collision

47 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is +80 ms and of m2 is -40 ms After the collision the velocity of m1 is +50ms What is the velocity of m2

48 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is -120 ms and of m2 is +80 ms After the collision the velocity of m1 is +90ms What is the velocity of m2

49 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is +20 ms and of m2 is +90 ms After the collision what will be the velocity of m1

50 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is +20 ms and of m2 is +90 ms After the collision what will be the velocity of m2

51 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +10 ms and m2 is initially at rest After the collision what will be the velocity of m2

52 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +10 ms and m1 is initially at rest After the collision what will be the velocity of m2

53 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 10 mph and that of the baseball is 30 mph What is the speed of the ball leaving the bat

54 Two objects have an elastic collision Before the collision they approach one another with a velocity of 18 ms With what velocity will they be separating after the collision

55 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is +60 ms and of m2 is +40 ms After the collision the velocity of m1 is +50ms What is the velocity of m2

56 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is -50 ms and of m2 is +80 ms After the collision the velocity of m1 is +70ms What is the velocity of m2

57 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m1

58 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m2

59 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +20 ms and m2 is initially at rest After the collision what will be the velocity of m2

60 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +20 ms and m1 is initially at rest After the collision what will be the velocity of m2

61 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 25 mph and that of the baseball is 80 mph What is the speed of the ball leaving the bat

Elastic Collision Problems (with masses)

62 A ball of mass 034 kg moving with a speed of 27 ms to the right collides head on with a 024 kg ball at rest If the collision is elastic what is the speed and direction of each ball after the collision

63 An ice puck of mass 054 kg moving with a speed of 5ms to the right collides with a 028 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each ball after the collision

64 An air track car with a mass of 075 kg and velocity of 85 ms to the right collides elastically with a 065 kg car moving to the left with a velocity of 72 ms If the collision is elastic what is the speed and direction of each ball after the collision

65 An air track car with a mass of 085 kg and velocity of 34 ms to the right collides elastically with

a 095 kg car moving to the left with a velocity of 49 ms If the collision is elastic what is the speed and direction of each ball after the collision

66 A ball of mass 65 kg moving with a speed of 15 ms to the right collides head-on with a 35 kg ball which is at rest If the collision is elastic what is the speed and direction of each ball after the collision

67 An ice puck of mass 75 kg moving with a speed of 18 ms to the right collides with a 25 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each mass after the collision

Change of Momentum and Impulse

68 A 1200 kg car accelerates from 13 ms to 17 ms Find the change in momentum of the car

69 A small object with a momentum of 6 kgmiddotms to the west approaches head-on a large object

at rest The small object bounces straight back with a momentum of 5 kgmiddotms What is the change in the momentum of the small object What is the impulse exerted on the small ball What is the impulse exerted on the large object

70 A 003 kg golf ball is hit off the tee at a speed of 34 ms The golf club was in contact with the

ball for 0003 s What is the average force on ball by the golf club

71 A toy rocket achieves a velocity of 55 ms after 3 s when fired straight up If the average force exerted by the engine is 28 N what is the toyrsquos mass

72 A 15000 kg air jet accelerates from rest to 45 ms before it takes off What is the change in

momentum of the jet

73 A 0025 kg piece of clay is thrown into a wall and has a speed of 9 ms before it strikes the wall Find the change in momentum of the clay and the impulse exerted on the clay if it does not bounce from the wall

74 A small bouncy ball with a momentum of 8 kgmiddotms to the left approaches head-on a large door at rest The ball bounces straight back with a momentum of 6 kgmiddotms What is the change in the momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the door

75 A 007 kg tennis ball leaves a racket with a speed of 56 ms If the ball is in contact with the racket for 004 s what is the average force on the ball by the racket

76 A 0145 kg baseball reaches a speed of 36 ms when a bat strikes If the average force of 500 N was applied on the ball by the bat what is the impact time

77 A 017 kg hockey puck slows down from 54 ms to 35 ms when it slides on horizontal ice

surface Find the change in momentum of the puck

78 A 001 kg bullet is fired at 250 ms into a wooden block that is fixed The bullet emerges from the block with a speed of 120 ms What is the change in momentum of the bullet

79 A 005 kg tennis ball moves at a speed of 10 ms and is struck by a racket causing it to rebound in the opposite direction at a speed 16 ms What is the change in momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the racket

80 A 025 kg beach ball rolling at a speed of 7 ms collides with a heavy exercise ball at rest The beach ball bounces straight back with a speed of 4 ms That is the change in momentum of the beach ball What is the impulse exerted on the beach ball What is the impulse exerted on the exercise ball

81 A 016 kg hockey puck is moving on an icy horizontal surface with a speed of 5 ms A player

strikes the puck by a hockey stick after the impact the puck moves in opposite direction with a speed of 9 ms If the puck was in contact with the stick for 0005 s what is the average force on the puck by the stick

82 A constant force of 12 N acts for 5 s on a 5 kg object What is the change in objectrsquos velocity

83 A small object with a mass of 1 kg moves in a circular path with a constant speed of 5 ms

What is the change in momentum during frac12 of period one period

General Problems

84 The diagram above shows a ballistic pendulum A 10 g bullet is fired into the suspended 2 kg

block of wood and remains embedded inside it (a perfectly inelastic collision) After the impact of the bullet the block swings up to a maximum height h If the initial speed of the bullet was 35 ms

a What was the momentum of the bullet before the collision

b What was the kinetic energy of the bullet before the collision

c What was the velocity of the bullet-block system just after the collision

d What was the total kinetic energy of the bullet-block system after the collision

e What is the maximum possible potential energy of the bullet-block system when it reaches its maximum height

f What is the maximum possible height of the bullet-block system

A B

85 Two objects A and B with masses of 32 kg and 18 kg move on a frictionless horizontal surface Object A moves to the right at a constant speed of 51 ms while object B moves to the right at a constant speed 14 ms They collide and stick together (a perfectly inelastic collision)

a Determine the total momentum of the system (both objects) before the collision

b Determine the total kinetic energy of the system before the collision

c Find the speed of the two objects after the collision

d Find the total kinetic energy of the system after the collision

e Is the kinetic energy of the system conserved Explain

86 A small cube with a mass of 25 g slides along a frictionless horizontal surface at a constant speed of 18 ms until it collides with and sticks to a large wooden 35 kg block The large block is attached to the left end of a spring with a spring constant of 100 Nm as shown above

a What is the momentum of the cube before the collision

b What is the kinetic energy of the cube before the collision

c Find the speed of the combined cube and block system just after the collision

d Find the kinetic energy of the cube-block system just after the collision

e What is the maximum potential energy that can be stored in the spring due to this collision

f How far will the cube-block system move before it stops

87 A track consists of a frictionless incline plane which is a height of 05 m and a rough horizontal

section with a coefficient of kinetic friction 002 Block A whose mass is15 kg is released from the top of the incline plane slides down and collides instantaneously and inelastically with identical block B at the lowest point The two blocks move to the right through the rough section of the track until they stop

a Determine the initial potential energy of block A

b Determine the kinetic energy of block A at the lowest point just before the collision

c Find the speed of the two blocks just after the collision

d Find the kinetic energy of the two blocks just after the collision

e How far will the two blocks travel on the rough section of the track

f How much work will the friction force do during this time

88 A bullet of mass 001 kg is moving horizontally with a speed of 100 ms when it hits a block of mass 2 kg that is at rest on a horizontal surface with a coefficient of friction of 04 After the collision the bullet becomes embedded in the block

a What is the net momentum of the bullet-block system before the collision b What is the net momentum of the bullet-block system after the collision c What is the speed of the bullet-block system after the collision d Find the total energy of the bullet-block system before the collision e Find the total energy of the bullet-block system after the collision f Is the total energy conserved during the collision g Find the maximum traveled distance of the bullet-block after the collision

89 A 35 kg child moving at 5 ms jumps onto a 40 kg sled that is initially at rest on a horizontal ice surface with the coefficient of friction of 002

a Determine the total momentum of the child-sled system before the child jumps onto the sled

b Determine the total momentum of the child-sled system after the child jumps onto the sled

c Determine the velocity of the child-sled system after the child jumps onto the sled

d Determine the total energy of the child-sled system before the child jumps onto the sled

e Determine the total energy of the child-sled system after the child jumps onto the sled

f Determine the maximum horizontal distance that child-sled can go after the child jumps onto the sled

90 A 10 g piece of sticky clay moving horizontally with a speed of 12 ms strikes a pendulum bob and sticks to the bob The pendulum bob has a mass of 50 g and it is suspended from a 07 m string

a Find the momentum of the clay before the collision

b Find the momentum of the clay-bob system after the collision

c Find the velocity of the clay-bob system after the collision

d Find the kinetic energy of the clay-bob system after the collision

e Find the maximum height of the clay-bob system that they deflect after the collision

f What velocity should the clay have before the collision in order for the clay-bob system to complete one circle

91 As shown above a 035 kg cart is moving on a horizontal frictionless track with a speed of 5 ms

when it hits and sticks to a 16 kg cart initially at rest on the track The 16 kg cart is connected to one end of a massless spring with a spring constant 80 Nm

a Determine the momentum of the 035 kg cart before the collision b Determine the kinetic energy of the 035 kg cart before the collision c Determine the momentum of the carts after the collision d Determine the kinetic energy of the carts after the collision e Is the kinetic energy conserved during the collision Explain you reasoning f Determine the maximum displacement of the spring after the collision

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

Chapter Problems Momentum of a Single Object

13 What is the momentum of a 3000 kg truck traveling at 25 ms

14 A 1500 kg ferryboat has a momentum of 25000 kgmiddotms What is the speed of the ferryboat

15 A car travels at a constant speed of 24 ms and has a momentum of 28800 kgmiddotms What is the

mass of the car

16 An 8 kg bowling ball rolls at a constant speed of 3 ms What is the momentum of the ball

17 A bicyclist travels at a constant speed of 7 ms What is the total mass of the bicycle and the boy when the total momentum is 490 kgmiddotms

18 When a 45 kg cannon ball leaves a barrel it has a momentum of 14000 kgmiddotms What is the speed of the ball at the end of the barrel

19 A 45 kg woman runs at a speed of 56 ms What is her momentum

20 A certain bowling ball rolls at a constant speed of 5 ms If the momentum of the ball is 425

kgmiddotms what is its mass

21 What is the speed of a 025 kg arrow with a momentum of 8 kgms

22 A 1500 kg car travels 400 m in 12 s What is its momentum

23 An electron has a mass of 91x10-31 kg What is its momentum if it is travelling at a speed of 35x106 ms

24 A 3 kg stone is dropped from a height of 4 m What is its momentum as it strikes the ground

Momentum of a System of Objects

25 Determine the momentum of a system that consists of two objects One object m1 has a mass

of 6 kg and a velocity of 13 ms towards the east and a second object m2 has a mass of 14 kg and a velocity of 7 ms in that same direction

26 Determine the momentum of a system that consists of two objects One object m1 has a mass of 6 kg and a velocity of 13 ms in the direction of the positive x-axis and a second object m2 has a mass of 14 kg and a velocity 7 ms in the direction of the negative x-axis

27 Determine the momentum of a system that consists of three objects One object m1 has a mass

of 7 kg and a velocity 23 ms towards the north a second object m2 has a mass of 9 kg and a velocity 7 ms towards the north and the third object m3 has a mass of 5 kg and a velocity of 42 ms towards the south

28 Determine the momentum of a system of the two objects One object m1 has a mass of 35 kg and a velocity of 37 ms towards the east and the second object m2 has a mass of 57 kg and a velocity of 43 ms towards the west

29 Determine the momentum of a system of the two objects One object m1 has a mass of 35 kg

and a velocity of 37 ms towards the north and the second object m2 has a mass of 57 kg and a velocity of 43 ms towards the south

30 Determine the momentum of a system that consists of three objects One object m1 has a mass

of 12 kg and a velocity 120 ms towards the east a second object m2 has a mass of 25 kg and a velocity 18 ms towards the west and the third object m3 has a mass of 1 kg and a velocity of 350 ms towards the east

Conservation of Momentum and Perfectly Inelastic Collisions

31 A 13500 kg railroad freight car travels on a level track at a speed of 45 ms It collides and

couples with a 25000 kg second car initially at rest and with brakes released What is the speed of the two cars after collision

32 A 40 kg girl skates at 35 ms on ice toward her 65 kg friend who is standing still with open arms As they collide and hold each other what is the speed of the couple

33 A 50 kg boy jumps off the front of a 15 kg skateboard moving forward Find the skateboardrsquos

velocity immediately after the boy jumps assuming that the skateboardrsquos initial velocity is 35 ms and the boyrsquos velocity when jumping off the front is 5 ms

34 A 001 kg bullet has a speed of 700 ms before it strikes a 095 kg wooden block that is stationary on a horizontal frictionless surface and remains inside of it What is the speed of the block after the bullet becomes embedded in it

35 A cannon ball with a mass of 100 kg flies in horizontal direction with a speed of 600 ms and strikes a railroad freight car filled with sand and initially at rest The total mass of the car and sand is 25600 kg Find the speed of the car after the ball becomes embedded it the sand

36 A 001 kg bullet is fired at a 05 kg block initially at rest The bullet moving with an initial speed of

400 ms emerges from the block with a speed of 300 ms What is the speed of the block after the collision

37 A 50 kg boy jumps off the back of a 15 kg skateboard moving forward Find the skateboardrsquos velocity immediately after the boy jumps assuming that the skateboardrsquos initial velocity is 35 ms and the boyrsquos velocity when jumping off the back is 5 ms

38 Two football players with mass 85 kg and 110 kg run directly toward each other with speeds 4

ms and 7 ms respectively If they grab each other as they collide what is the combined speed of the players just after the collision

39 An air track car with a mass of 055 kg and velocity of 58 ms to the right collides and couples with a 045 kg car moving to the left with a velocity of 39 ms What is the combined velocity of the cars just after the collision

40 An air track car with a mass of 025 kg and velocity of 34 ms to the right collides and couples with a 045 kg car moving to the left with a velocity of 39 ms What is the combined velocity of the cars just after the collision

41 A 15000 kg railroad car travels on a horizontal track with a constant speed of 12 ms A 6000 kg load is dropped onto the car What will be the carrsquos speed

42 A 55 kg skater at rest on a frictionless rink throws a 3 kg ball giving the ball a velocity of 8 ms What is the velocity of the skater immediately after

43 A 0015 kg bullet is fired at a 15 kg block initially at rest The bullet moving with an initial speed of 500 ms emerges from the block with a speed of 400 ms What is the speed of the block after the collision

44 A 40 kg surfer jumps off the front of a 20 kg surfboard moving forward Find the surfboardrsquos

velocity immediately after the girl jumps assuming that the surfboardrsquos initial velocity is 8 ms and the girlrsquos velocity when jumping off the front is 3 ms

45 A 40 kg surfer jumps off the back of a 20 kg surfboard moving forward Find the surfboardrsquos velocity immediately after the girl jumps assuming that the surfboardrsquos initial velocity is 8 ms and the girlrsquos velocity when jumping off the back is 3 ms

Elastic Collision Problems (without masses)

46 Two objects have an elastic collision Before the collision they approach one another with a velocity of 45 ms With what velocity will they be separating after the collision

47 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is +80 ms and of m2 is -40 ms After the collision the velocity of m1 is +50ms What is the velocity of m2

48 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is -120 ms and of m2 is +80 ms After the collision the velocity of m1 is +90ms What is the velocity of m2

49 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is +20 ms and of m2 is +90 ms After the collision what will be the velocity of m1

50 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is +20 ms and of m2 is +90 ms After the collision what will be the velocity of m2

51 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +10 ms and m2 is initially at rest After the collision what will be the velocity of m2

52 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +10 ms and m1 is initially at rest After the collision what will be the velocity of m2

53 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 10 mph and that of the baseball is 30 mph What is the speed of the ball leaving the bat

54 Two objects have an elastic collision Before the collision they approach one another with a velocity of 18 ms With what velocity will they be separating after the collision

55 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is +60 ms and of m2 is +40 ms After the collision the velocity of m1 is +50ms What is the velocity of m2

56 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is -50 ms and of m2 is +80 ms After the collision the velocity of m1 is +70ms What is the velocity of m2

57 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m1

58 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m2

59 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +20 ms and m2 is initially at rest After the collision what will be the velocity of m2

60 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +20 ms and m1 is initially at rest After the collision what will be the velocity of m2

61 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 25 mph and that of the baseball is 80 mph What is the speed of the ball leaving the bat

Elastic Collision Problems (with masses)

62 A ball of mass 034 kg moving with a speed of 27 ms to the right collides head on with a 024 kg ball at rest If the collision is elastic what is the speed and direction of each ball after the collision

63 An ice puck of mass 054 kg moving with a speed of 5ms to the right collides with a 028 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each ball after the collision

64 An air track car with a mass of 075 kg and velocity of 85 ms to the right collides elastically with a 065 kg car moving to the left with a velocity of 72 ms If the collision is elastic what is the speed and direction of each ball after the collision

65 An air track car with a mass of 085 kg and velocity of 34 ms to the right collides elastically with

a 095 kg car moving to the left with a velocity of 49 ms If the collision is elastic what is the speed and direction of each ball after the collision

66 A ball of mass 65 kg moving with a speed of 15 ms to the right collides head-on with a 35 kg ball which is at rest If the collision is elastic what is the speed and direction of each ball after the collision

67 An ice puck of mass 75 kg moving with a speed of 18 ms to the right collides with a 25 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each mass after the collision

Change of Momentum and Impulse

68 A 1200 kg car accelerates from 13 ms to 17 ms Find the change in momentum of the car

69 A small object with a momentum of 6 kgmiddotms to the west approaches head-on a large object

at rest The small object bounces straight back with a momentum of 5 kgmiddotms What is the change in the momentum of the small object What is the impulse exerted on the small ball What is the impulse exerted on the large object

70 A 003 kg golf ball is hit off the tee at a speed of 34 ms The golf club was in contact with the

ball for 0003 s What is the average force on ball by the golf club

71 A toy rocket achieves a velocity of 55 ms after 3 s when fired straight up If the average force exerted by the engine is 28 N what is the toyrsquos mass

72 A 15000 kg air jet accelerates from rest to 45 ms before it takes off What is the change in

momentum of the jet

73 A 0025 kg piece of clay is thrown into a wall and has a speed of 9 ms before it strikes the wall Find the change in momentum of the clay and the impulse exerted on the clay if it does not bounce from the wall

74 A small bouncy ball with a momentum of 8 kgmiddotms to the left approaches head-on a large door at rest The ball bounces straight back with a momentum of 6 kgmiddotms What is the change in the momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the door

75 A 007 kg tennis ball leaves a racket with a speed of 56 ms If the ball is in contact with the racket for 004 s what is the average force on the ball by the racket

76 A 0145 kg baseball reaches a speed of 36 ms when a bat strikes If the average force of 500 N was applied on the ball by the bat what is the impact time

77 A 017 kg hockey puck slows down from 54 ms to 35 ms when it slides on horizontal ice

surface Find the change in momentum of the puck

78 A 001 kg bullet is fired at 250 ms into a wooden block that is fixed The bullet emerges from the block with a speed of 120 ms What is the change in momentum of the bullet

79 A 005 kg tennis ball moves at a speed of 10 ms and is struck by a racket causing it to rebound in the opposite direction at a speed 16 ms What is the change in momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the racket

80 A 025 kg beach ball rolling at a speed of 7 ms collides with a heavy exercise ball at rest The beach ball bounces straight back with a speed of 4 ms That is the change in momentum of the beach ball What is the impulse exerted on the beach ball What is the impulse exerted on the exercise ball

81 A 016 kg hockey puck is moving on an icy horizontal surface with a speed of 5 ms A player

strikes the puck by a hockey stick after the impact the puck moves in opposite direction with a speed of 9 ms If the puck was in contact with the stick for 0005 s what is the average force on the puck by the stick

82 A constant force of 12 N acts for 5 s on a 5 kg object What is the change in objectrsquos velocity

83 A small object with a mass of 1 kg moves in a circular path with a constant speed of 5 ms

What is the change in momentum during frac12 of period one period

General Problems

84 The diagram above shows a ballistic pendulum A 10 g bullet is fired into the suspended 2 kg

block of wood and remains embedded inside it (a perfectly inelastic collision) After the impact of the bullet the block swings up to a maximum height h If the initial speed of the bullet was 35 ms

a What was the momentum of the bullet before the collision

b What was the kinetic energy of the bullet before the collision

c What was the velocity of the bullet-block system just after the collision

d What was the total kinetic energy of the bullet-block system after the collision

e What is the maximum possible potential energy of the bullet-block system when it reaches its maximum height

f What is the maximum possible height of the bullet-block system

A B

85 Two objects A and B with masses of 32 kg and 18 kg move on a frictionless horizontal surface Object A moves to the right at a constant speed of 51 ms while object B moves to the right at a constant speed 14 ms They collide and stick together (a perfectly inelastic collision)

a Determine the total momentum of the system (both objects) before the collision

b Determine the total kinetic energy of the system before the collision

c Find the speed of the two objects after the collision

d Find the total kinetic energy of the system after the collision

e Is the kinetic energy of the system conserved Explain

86 A small cube with a mass of 25 g slides along a frictionless horizontal surface at a constant speed of 18 ms until it collides with and sticks to a large wooden 35 kg block The large block is attached to the left end of a spring with a spring constant of 100 Nm as shown above

a What is the momentum of the cube before the collision

b What is the kinetic energy of the cube before the collision

c Find the speed of the combined cube and block system just after the collision

d Find the kinetic energy of the cube-block system just after the collision

e What is the maximum potential energy that can be stored in the spring due to this collision

f How far will the cube-block system move before it stops

87 A track consists of a frictionless incline plane which is a height of 05 m and a rough horizontal

section with a coefficient of kinetic friction 002 Block A whose mass is15 kg is released from the top of the incline plane slides down and collides instantaneously and inelastically with identical block B at the lowest point The two blocks move to the right through the rough section of the track until they stop

a Determine the initial potential energy of block A

b Determine the kinetic energy of block A at the lowest point just before the collision

c Find the speed of the two blocks just after the collision

d Find the kinetic energy of the two blocks just after the collision

e How far will the two blocks travel on the rough section of the track

f How much work will the friction force do during this time

88 A bullet of mass 001 kg is moving horizontally with a speed of 100 ms when it hits a block of mass 2 kg that is at rest on a horizontal surface with a coefficient of friction of 04 After the collision the bullet becomes embedded in the block

a What is the net momentum of the bullet-block system before the collision b What is the net momentum of the bullet-block system after the collision c What is the speed of the bullet-block system after the collision d Find the total energy of the bullet-block system before the collision e Find the total energy of the bullet-block system after the collision f Is the total energy conserved during the collision g Find the maximum traveled distance of the bullet-block after the collision

89 A 35 kg child moving at 5 ms jumps onto a 40 kg sled that is initially at rest on a horizontal ice surface with the coefficient of friction of 002

a Determine the total momentum of the child-sled system before the child jumps onto the sled

b Determine the total momentum of the child-sled system after the child jumps onto the sled

c Determine the velocity of the child-sled system after the child jumps onto the sled

d Determine the total energy of the child-sled system before the child jumps onto the sled

e Determine the total energy of the child-sled system after the child jumps onto the sled

f Determine the maximum horizontal distance that child-sled can go after the child jumps onto the sled

90 A 10 g piece of sticky clay moving horizontally with a speed of 12 ms strikes a pendulum bob and sticks to the bob The pendulum bob has a mass of 50 g and it is suspended from a 07 m string

a Find the momentum of the clay before the collision

b Find the momentum of the clay-bob system after the collision

c Find the velocity of the clay-bob system after the collision

d Find the kinetic energy of the clay-bob system after the collision

e Find the maximum height of the clay-bob system that they deflect after the collision

f What velocity should the clay have before the collision in order for the clay-bob system to complete one circle

91 As shown above a 035 kg cart is moving on a horizontal frictionless track with a speed of 5 ms

when it hits and sticks to a 16 kg cart initially at rest on the track The 16 kg cart is connected to one end of a massless spring with a spring constant 80 Nm

a Determine the momentum of the 035 kg cart before the collision b Determine the kinetic energy of the 035 kg cart before the collision c Determine the momentum of the carts after the collision d Determine the kinetic energy of the carts after the collision e Is the kinetic energy conserved during the collision Explain you reasoning f Determine the maximum displacement of the spring after the collision

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

30 Determine the momentum of a system that consists of three objects One object m1 has a mass

of 12 kg and a velocity 120 ms towards the east a second object m2 has a mass of 25 kg and a velocity 18 ms towards the west and the third object m3 has a mass of 1 kg and a velocity of 350 ms towards the east

Conservation of Momentum and Perfectly Inelastic Collisions

31 A 13500 kg railroad freight car travels on a level track at a speed of 45 ms It collides and

couples with a 25000 kg second car initially at rest and with brakes released What is the speed of the two cars after collision

32 A 40 kg girl skates at 35 ms on ice toward her 65 kg friend who is standing still with open arms As they collide and hold each other what is the speed of the couple

33 A 50 kg boy jumps off the front of a 15 kg skateboard moving forward Find the skateboardrsquos

velocity immediately after the boy jumps assuming that the skateboardrsquos initial velocity is 35 ms and the boyrsquos velocity when jumping off the front is 5 ms

34 A 001 kg bullet has a speed of 700 ms before it strikes a 095 kg wooden block that is stationary on a horizontal frictionless surface and remains inside of it What is the speed of the block after the bullet becomes embedded in it

35 A cannon ball with a mass of 100 kg flies in horizontal direction with a speed of 600 ms and strikes a railroad freight car filled with sand and initially at rest The total mass of the car and sand is 25600 kg Find the speed of the car after the ball becomes embedded it the sand

36 A 001 kg bullet is fired at a 05 kg block initially at rest The bullet moving with an initial speed of

400 ms emerges from the block with a speed of 300 ms What is the speed of the block after the collision

37 A 50 kg boy jumps off the back of a 15 kg skateboard moving forward Find the skateboardrsquos velocity immediately after the boy jumps assuming that the skateboardrsquos initial velocity is 35 ms and the boyrsquos velocity when jumping off the back is 5 ms

38 Two football players with mass 85 kg and 110 kg run directly toward each other with speeds 4

ms and 7 ms respectively If they grab each other as they collide what is the combined speed of the players just after the collision

39 An air track car with a mass of 055 kg and velocity of 58 ms to the right collides and couples with a 045 kg car moving to the left with a velocity of 39 ms What is the combined velocity of the cars just after the collision

40 An air track car with a mass of 025 kg and velocity of 34 ms to the right collides and couples with a 045 kg car moving to the left with a velocity of 39 ms What is the combined velocity of the cars just after the collision

41 A 15000 kg railroad car travels on a horizontal track with a constant speed of 12 ms A 6000 kg load is dropped onto the car What will be the carrsquos speed

42 A 55 kg skater at rest on a frictionless rink throws a 3 kg ball giving the ball a velocity of 8 ms What is the velocity of the skater immediately after

43 A 0015 kg bullet is fired at a 15 kg block initially at rest The bullet moving with an initial speed of 500 ms emerges from the block with a speed of 400 ms What is the speed of the block after the collision

44 A 40 kg surfer jumps off the front of a 20 kg surfboard moving forward Find the surfboardrsquos

velocity immediately after the girl jumps assuming that the surfboardrsquos initial velocity is 8 ms and the girlrsquos velocity when jumping off the front is 3 ms

45 A 40 kg surfer jumps off the back of a 20 kg surfboard moving forward Find the surfboardrsquos velocity immediately after the girl jumps assuming that the surfboardrsquos initial velocity is 8 ms and the girlrsquos velocity when jumping off the back is 3 ms

Elastic Collision Problems (without masses)

46 Two objects have an elastic collision Before the collision they approach one another with a velocity of 45 ms With what velocity will they be separating after the collision

47 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is +80 ms and of m2 is -40 ms After the collision the velocity of m1 is +50ms What is the velocity of m2

48 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is -120 ms and of m2 is +80 ms After the collision the velocity of m1 is +90ms What is the velocity of m2

49 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is +20 ms and of m2 is +90 ms After the collision what will be the velocity of m1

50 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is +20 ms and of m2 is +90 ms After the collision what will be the velocity of m2

51 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +10 ms and m2 is initially at rest After the collision what will be the velocity of m2

52 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +10 ms and m1 is initially at rest After the collision what will be the velocity of m2

53 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 10 mph and that of the baseball is 30 mph What is the speed of the ball leaving the bat

54 Two objects have an elastic collision Before the collision they approach one another with a velocity of 18 ms With what velocity will they be separating after the collision

55 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is +60 ms and of m2 is +40 ms After the collision the velocity of m1 is +50ms What is the velocity of m2

56 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is -50 ms and of m2 is +80 ms After the collision the velocity of m1 is +70ms What is the velocity of m2

57 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m1

58 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m2

59 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +20 ms and m2 is initially at rest After the collision what will be the velocity of m2

60 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +20 ms and m1 is initially at rest After the collision what will be the velocity of m2

61 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 25 mph and that of the baseball is 80 mph What is the speed of the ball leaving the bat

Elastic Collision Problems (with masses)

62 A ball of mass 034 kg moving with a speed of 27 ms to the right collides head on with a 024 kg ball at rest If the collision is elastic what is the speed and direction of each ball after the collision

63 An ice puck of mass 054 kg moving with a speed of 5ms to the right collides with a 028 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each ball after the collision

64 An air track car with a mass of 075 kg and velocity of 85 ms to the right collides elastically with a 065 kg car moving to the left with a velocity of 72 ms If the collision is elastic what is the speed and direction of each ball after the collision

65 An air track car with a mass of 085 kg and velocity of 34 ms to the right collides elastically with

a 095 kg car moving to the left with a velocity of 49 ms If the collision is elastic what is the speed and direction of each ball after the collision

66 A ball of mass 65 kg moving with a speed of 15 ms to the right collides head-on with a 35 kg ball which is at rest If the collision is elastic what is the speed and direction of each ball after the collision

67 An ice puck of mass 75 kg moving with a speed of 18 ms to the right collides with a 25 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each mass after the collision

Change of Momentum and Impulse

68 A 1200 kg car accelerates from 13 ms to 17 ms Find the change in momentum of the car

69 A small object with a momentum of 6 kgmiddotms to the west approaches head-on a large object

at rest The small object bounces straight back with a momentum of 5 kgmiddotms What is the change in the momentum of the small object What is the impulse exerted on the small ball What is the impulse exerted on the large object

70 A 003 kg golf ball is hit off the tee at a speed of 34 ms The golf club was in contact with the

ball for 0003 s What is the average force on ball by the golf club

71 A toy rocket achieves a velocity of 55 ms after 3 s when fired straight up If the average force exerted by the engine is 28 N what is the toyrsquos mass

72 A 15000 kg air jet accelerates from rest to 45 ms before it takes off What is the change in

momentum of the jet

73 A 0025 kg piece of clay is thrown into a wall and has a speed of 9 ms before it strikes the wall Find the change in momentum of the clay and the impulse exerted on the clay if it does not bounce from the wall

74 A small bouncy ball with a momentum of 8 kgmiddotms to the left approaches head-on a large door at rest The ball bounces straight back with a momentum of 6 kgmiddotms What is the change in the momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the door

75 A 007 kg tennis ball leaves a racket with a speed of 56 ms If the ball is in contact with the racket for 004 s what is the average force on the ball by the racket

76 A 0145 kg baseball reaches a speed of 36 ms when a bat strikes If the average force of 500 N was applied on the ball by the bat what is the impact time

77 A 017 kg hockey puck slows down from 54 ms to 35 ms when it slides on horizontal ice

surface Find the change in momentum of the puck

78 A 001 kg bullet is fired at 250 ms into a wooden block that is fixed The bullet emerges from the block with a speed of 120 ms What is the change in momentum of the bullet

79 A 005 kg tennis ball moves at a speed of 10 ms and is struck by a racket causing it to rebound in the opposite direction at a speed 16 ms What is the change in momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the racket

80 A 025 kg beach ball rolling at a speed of 7 ms collides with a heavy exercise ball at rest The beach ball bounces straight back with a speed of 4 ms That is the change in momentum of the beach ball What is the impulse exerted on the beach ball What is the impulse exerted on the exercise ball

81 A 016 kg hockey puck is moving on an icy horizontal surface with a speed of 5 ms A player

strikes the puck by a hockey stick after the impact the puck moves in opposite direction with a speed of 9 ms If the puck was in contact with the stick for 0005 s what is the average force on the puck by the stick

82 A constant force of 12 N acts for 5 s on a 5 kg object What is the change in objectrsquos velocity

83 A small object with a mass of 1 kg moves in a circular path with a constant speed of 5 ms

What is the change in momentum during frac12 of period one period

General Problems

84 The diagram above shows a ballistic pendulum A 10 g bullet is fired into the suspended 2 kg

block of wood and remains embedded inside it (a perfectly inelastic collision) After the impact of the bullet the block swings up to a maximum height h If the initial speed of the bullet was 35 ms

a What was the momentum of the bullet before the collision

b What was the kinetic energy of the bullet before the collision

c What was the velocity of the bullet-block system just after the collision

d What was the total kinetic energy of the bullet-block system after the collision

e What is the maximum possible potential energy of the bullet-block system when it reaches its maximum height

f What is the maximum possible height of the bullet-block system

A B

85 Two objects A and B with masses of 32 kg and 18 kg move on a frictionless horizontal surface Object A moves to the right at a constant speed of 51 ms while object B moves to the right at a constant speed 14 ms They collide and stick together (a perfectly inelastic collision)

a Determine the total momentum of the system (both objects) before the collision

b Determine the total kinetic energy of the system before the collision

c Find the speed of the two objects after the collision

d Find the total kinetic energy of the system after the collision

e Is the kinetic energy of the system conserved Explain

86 A small cube with a mass of 25 g slides along a frictionless horizontal surface at a constant speed of 18 ms until it collides with and sticks to a large wooden 35 kg block The large block is attached to the left end of a spring with a spring constant of 100 Nm as shown above

a What is the momentum of the cube before the collision

b What is the kinetic energy of the cube before the collision

c Find the speed of the combined cube and block system just after the collision

d Find the kinetic energy of the cube-block system just after the collision

e What is the maximum potential energy that can be stored in the spring due to this collision

f How far will the cube-block system move before it stops

87 A track consists of a frictionless incline plane which is a height of 05 m and a rough horizontal

section with a coefficient of kinetic friction 002 Block A whose mass is15 kg is released from the top of the incline plane slides down and collides instantaneously and inelastically with identical block B at the lowest point The two blocks move to the right through the rough section of the track until they stop

a Determine the initial potential energy of block A

b Determine the kinetic energy of block A at the lowest point just before the collision

c Find the speed of the two blocks just after the collision

d Find the kinetic energy of the two blocks just after the collision

e How far will the two blocks travel on the rough section of the track

f How much work will the friction force do during this time

88 A bullet of mass 001 kg is moving horizontally with a speed of 100 ms when it hits a block of mass 2 kg that is at rest on a horizontal surface with a coefficient of friction of 04 After the collision the bullet becomes embedded in the block

a What is the net momentum of the bullet-block system before the collision b What is the net momentum of the bullet-block system after the collision c What is the speed of the bullet-block system after the collision d Find the total energy of the bullet-block system before the collision e Find the total energy of the bullet-block system after the collision f Is the total energy conserved during the collision g Find the maximum traveled distance of the bullet-block after the collision

89 A 35 kg child moving at 5 ms jumps onto a 40 kg sled that is initially at rest on a horizontal ice surface with the coefficient of friction of 002

a Determine the total momentum of the child-sled system before the child jumps onto the sled

b Determine the total momentum of the child-sled system after the child jumps onto the sled

c Determine the velocity of the child-sled system after the child jumps onto the sled

d Determine the total energy of the child-sled system before the child jumps onto the sled

e Determine the total energy of the child-sled system after the child jumps onto the sled

f Determine the maximum horizontal distance that child-sled can go after the child jumps onto the sled

90 A 10 g piece of sticky clay moving horizontally with a speed of 12 ms strikes a pendulum bob and sticks to the bob The pendulum bob has a mass of 50 g and it is suspended from a 07 m string

a Find the momentum of the clay before the collision

b Find the momentum of the clay-bob system after the collision

c Find the velocity of the clay-bob system after the collision

d Find the kinetic energy of the clay-bob system after the collision

e Find the maximum height of the clay-bob system that they deflect after the collision

f What velocity should the clay have before the collision in order for the clay-bob system to complete one circle

91 As shown above a 035 kg cart is moving on a horizontal frictionless track with a speed of 5 ms

when it hits and sticks to a 16 kg cart initially at rest on the track The 16 kg cart is connected to one end of a massless spring with a spring constant 80 Nm

a Determine the momentum of the 035 kg cart before the collision b Determine the kinetic energy of the 035 kg cart before the collision c Determine the momentum of the carts after the collision d Determine the kinetic energy of the carts after the collision e Is the kinetic energy conserved during the collision Explain you reasoning f Determine the maximum displacement of the spring after the collision

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

43 A 0015 kg bullet is fired at a 15 kg block initially at rest The bullet moving with an initial speed of 500 ms emerges from the block with a speed of 400 ms What is the speed of the block after the collision

44 A 40 kg surfer jumps off the front of a 20 kg surfboard moving forward Find the surfboardrsquos

velocity immediately after the girl jumps assuming that the surfboardrsquos initial velocity is 8 ms and the girlrsquos velocity when jumping off the front is 3 ms

45 A 40 kg surfer jumps off the back of a 20 kg surfboard moving forward Find the surfboardrsquos velocity immediately after the girl jumps assuming that the surfboardrsquos initial velocity is 8 ms and the girlrsquos velocity when jumping off the back is 3 ms

Elastic Collision Problems (without masses)

46 Two objects have an elastic collision Before the collision they approach one another with a velocity of 45 ms With what velocity will they be separating after the collision

47 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is +80 ms and of m2 is -40 ms After the collision the velocity of m1 is +50ms What is the velocity of m2

48 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is -120 ms and of m2 is +80 ms After the collision the velocity of m1 is +90ms What is the velocity of m2

49 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is +20 ms and of m2 is +90 ms After the collision what will be the velocity of m1

50 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is +20 ms and of m2 is +90 ms After the collision what will be the velocity of m2

51 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +10 ms and m2 is initially at rest After the collision what will be the velocity of m2

52 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +10 ms and m1 is initially at rest After the collision what will be the velocity of m2

53 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 10 mph and that of the baseball is 30 mph What is the speed of the ball leaving the bat

54 Two objects have an elastic collision Before the collision they approach one another with a velocity of 18 ms With what velocity will they be separating after the collision

55 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is +60 ms and of m2 is +40 ms After the collision the velocity of m1 is +50ms What is the velocity of m2

56 Two objects m1 and m2 have an elastic collision The initial velocity of m1 is -50 ms and of m2 is +80 ms After the collision the velocity of m1 is +70ms What is the velocity of m2

57 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m1

58 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m2

59 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +20 ms and m2 is initially at rest After the collision what will be the velocity of m2

60 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +20 ms and m1 is initially at rest After the collision what will be the velocity of m2

61 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 25 mph and that of the baseball is 80 mph What is the speed of the ball leaving the bat

Elastic Collision Problems (with masses)

62 A ball of mass 034 kg moving with a speed of 27 ms to the right collides head on with a 024 kg ball at rest If the collision is elastic what is the speed and direction of each ball after the collision

63 An ice puck of mass 054 kg moving with a speed of 5ms to the right collides with a 028 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each ball after the collision

64 An air track car with a mass of 075 kg and velocity of 85 ms to the right collides elastically with a 065 kg car moving to the left with a velocity of 72 ms If the collision is elastic what is the speed and direction of each ball after the collision

65 An air track car with a mass of 085 kg and velocity of 34 ms to the right collides elastically with

a 095 kg car moving to the left with a velocity of 49 ms If the collision is elastic what is the speed and direction of each ball after the collision

66 A ball of mass 65 kg moving with a speed of 15 ms to the right collides head-on with a 35 kg ball which is at rest If the collision is elastic what is the speed and direction of each ball after the collision

67 An ice puck of mass 75 kg moving with a speed of 18 ms to the right collides with a 25 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each mass after the collision

Change of Momentum and Impulse

68 A 1200 kg car accelerates from 13 ms to 17 ms Find the change in momentum of the car

69 A small object with a momentum of 6 kgmiddotms to the west approaches head-on a large object

at rest The small object bounces straight back with a momentum of 5 kgmiddotms What is the change in the momentum of the small object What is the impulse exerted on the small ball What is the impulse exerted on the large object

70 A 003 kg golf ball is hit off the tee at a speed of 34 ms The golf club was in contact with the

ball for 0003 s What is the average force on ball by the golf club

71 A toy rocket achieves a velocity of 55 ms after 3 s when fired straight up If the average force exerted by the engine is 28 N what is the toyrsquos mass

72 A 15000 kg air jet accelerates from rest to 45 ms before it takes off What is the change in

momentum of the jet

73 A 0025 kg piece of clay is thrown into a wall and has a speed of 9 ms before it strikes the wall Find the change in momentum of the clay and the impulse exerted on the clay if it does not bounce from the wall

74 A small bouncy ball with a momentum of 8 kgmiddotms to the left approaches head-on a large door at rest The ball bounces straight back with a momentum of 6 kgmiddotms What is the change in the momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the door

75 A 007 kg tennis ball leaves a racket with a speed of 56 ms If the ball is in contact with the racket for 004 s what is the average force on the ball by the racket

76 A 0145 kg baseball reaches a speed of 36 ms when a bat strikes If the average force of 500 N was applied on the ball by the bat what is the impact time

77 A 017 kg hockey puck slows down from 54 ms to 35 ms when it slides on horizontal ice

surface Find the change in momentum of the puck

78 A 001 kg bullet is fired at 250 ms into a wooden block that is fixed The bullet emerges from the block with a speed of 120 ms What is the change in momentum of the bullet

79 A 005 kg tennis ball moves at a speed of 10 ms and is struck by a racket causing it to rebound in the opposite direction at a speed 16 ms What is the change in momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the racket

80 A 025 kg beach ball rolling at a speed of 7 ms collides with a heavy exercise ball at rest The beach ball bounces straight back with a speed of 4 ms That is the change in momentum of the beach ball What is the impulse exerted on the beach ball What is the impulse exerted on the exercise ball

81 A 016 kg hockey puck is moving on an icy horizontal surface with a speed of 5 ms A player

strikes the puck by a hockey stick after the impact the puck moves in opposite direction with a speed of 9 ms If the puck was in contact with the stick for 0005 s what is the average force on the puck by the stick

82 A constant force of 12 N acts for 5 s on a 5 kg object What is the change in objectrsquos velocity

83 A small object with a mass of 1 kg moves in a circular path with a constant speed of 5 ms

What is the change in momentum during frac12 of period one period

General Problems

84 The diagram above shows a ballistic pendulum A 10 g bullet is fired into the suspended 2 kg

block of wood and remains embedded inside it (a perfectly inelastic collision) After the impact of the bullet the block swings up to a maximum height h If the initial speed of the bullet was 35 ms

a What was the momentum of the bullet before the collision

b What was the kinetic energy of the bullet before the collision

c What was the velocity of the bullet-block system just after the collision

d What was the total kinetic energy of the bullet-block system after the collision

e What is the maximum possible potential energy of the bullet-block system when it reaches its maximum height

f What is the maximum possible height of the bullet-block system

A B

85 Two objects A and B with masses of 32 kg and 18 kg move on a frictionless horizontal surface Object A moves to the right at a constant speed of 51 ms while object B moves to the right at a constant speed 14 ms They collide and stick together (a perfectly inelastic collision)

a Determine the total momentum of the system (both objects) before the collision

b Determine the total kinetic energy of the system before the collision

c Find the speed of the two objects after the collision

d Find the total kinetic energy of the system after the collision

e Is the kinetic energy of the system conserved Explain

86 A small cube with a mass of 25 g slides along a frictionless horizontal surface at a constant speed of 18 ms until it collides with and sticks to a large wooden 35 kg block The large block is attached to the left end of a spring with a spring constant of 100 Nm as shown above

a What is the momentum of the cube before the collision

b What is the kinetic energy of the cube before the collision

c Find the speed of the combined cube and block system just after the collision

d Find the kinetic energy of the cube-block system just after the collision

e What is the maximum potential energy that can be stored in the spring due to this collision

f How far will the cube-block system move before it stops

87 A track consists of a frictionless incline plane which is a height of 05 m and a rough horizontal

section with a coefficient of kinetic friction 002 Block A whose mass is15 kg is released from the top of the incline plane slides down and collides instantaneously and inelastically with identical block B at the lowest point The two blocks move to the right through the rough section of the track until they stop

a Determine the initial potential energy of block A

b Determine the kinetic energy of block A at the lowest point just before the collision

c Find the speed of the two blocks just after the collision

d Find the kinetic energy of the two blocks just after the collision

e How far will the two blocks travel on the rough section of the track

f How much work will the friction force do during this time

88 A bullet of mass 001 kg is moving horizontally with a speed of 100 ms when it hits a block of mass 2 kg that is at rest on a horizontal surface with a coefficient of friction of 04 After the collision the bullet becomes embedded in the block

a What is the net momentum of the bullet-block system before the collision b What is the net momentum of the bullet-block system after the collision c What is the speed of the bullet-block system after the collision d Find the total energy of the bullet-block system before the collision e Find the total energy of the bullet-block system after the collision f Is the total energy conserved during the collision g Find the maximum traveled distance of the bullet-block after the collision

89 A 35 kg child moving at 5 ms jumps onto a 40 kg sled that is initially at rest on a horizontal ice surface with the coefficient of friction of 002

a Determine the total momentum of the child-sled system before the child jumps onto the sled

b Determine the total momentum of the child-sled system after the child jumps onto the sled

c Determine the velocity of the child-sled system after the child jumps onto the sled

d Determine the total energy of the child-sled system before the child jumps onto the sled

e Determine the total energy of the child-sled system after the child jumps onto the sled

f Determine the maximum horizontal distance that child-sled can go after the child jumps onto the sled

90 A 10 g piece of sticky clay moving horizontally with a speed of 12 ms strikes a pendulum bob and sticks to the bob The pendulum bob has a mass of 50 g and it is suspended from a 07 m string

a Find the momentum of the clay before the collision

b Find the momentum of the clay-bob system after the collision

c Find the velocity of the clay-bob system after the collision

d Find the kinetic energy of the clay-bob system after the collision

e Find the maximum height of the clay-bob system that they deflect after the collision

f What velocity should the clay have before the collision in order for the clay-bob system to complete one circle

91 As shown above a 035 kg cart is moving on a horizontal frictionless track with a speed of 5 ms

when it hits and sticks to a 16 kg cart initially at rest on the track The 16 kg cart is connected to one end of a massless spring with a spring constant 80 Nm

a Determine the momentum of the 035 kg cart before the collision b Determine the kinetic energy of the 035 kg cart before the collision c Determine the momentum of the carts after the collision d Determine the kinetic energy of the carts after the collision e Is the kinetic energy conserved during the collision Explain you reasoning f Determine the maximum displacement of the spring after the collision

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

58 Two objects with identical masses m1 and m2 have an elastic collision The initial velocity of m1 is -90 ms and of m2 is -30 ms After the collision what will be the velocity of m2

59 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m1 is +20 ms and m2 is initially at rest After the collision what will be the velocity of m2

60 Two objects have an elastic collision The mass of m1 is much greater than that of m2 so that the velocity of m1 is barely affected by the collision The initial velocity of m2 is +20 ms and m1 is initially at rest After the collision what will be the velocity of m2

61 A bat has a nearly elastic collision with a baseball The velocity of the bat is barely affected by the collision The initial velocity of the bat is 25 mph and that of the baseball is 80 mph What is the speed of the ball leaving the bat

Elastic Collision Problems (with masses)

62 A ball of mass 034 kg moving with a speed of 27 ms to the right collides head on with a 024 kg ball at rest If the collision is elastic what is the speed and direction of each ball after the collision

63 An ice puck of mass 054 kg moving with a speed of 5ms to the right collides with a 028 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each ball after the collision

64 An air track car with a mass of 075 kg and velocity of 85 ms to the right collides elastically with a 065 kg car moving to the left with a velocity of 72 ms If the collision is elastic what is the speed and direction of each ball after the collision

65 An air track car with a mass of 085 kg and velocity of 34 ms to the right collides elastically with

a 095 kg car moving to the left with a velocity of 49 ms If the collision is elastic what is the speed and direction of each ball after the collision

66 A ball of mass 65 kg moving with a speed of 15 ms to the right collides head-on with a 35 kg ball which is at rest If the collision is elastic what is the speed and direction of each ball after the collision

67 An ice puck of mass 75 kg moving with a speed of 18 ms to the right collides with a 25 kg piece of ice moving with a speed of 42 ms to the right If the collision is elastic what is the speed and direction of each mass after the collision

Change of Momentum and Impulse

68 A 1200 kg car accelerates from 13 ms to 17 ms Find the change in momentum of the car

69 A small object with a momentum of 6 kgmiddotms to the west approaches head-on a large object

at rest The small object bounces straight back with a momentum of 5 kgmiddotms What is the change in the momentum of the small object What is the impulse exerted on the small ball What is the impulse exerted on the large object

70 A 003 kg golf ball is hit off the tee at a speed of 34 ms The golf club was in contact with the

ball for 0003 s What is the average force on ball by the golf club

71 A toy rocket achieves a velocity of 55 ms after 3 s when fired straight up If the average force exerted by the engine is 28 N what is the toyrsquos mass

72 A 15000 kg air jet accelerates from rest to 45 ms before it takes off What is the change in

momentum of the jet

73 A 0025 kg piece of clay is thrown into a wall and has a speed of 9 ms before it strikes the wall Find the change in momentum of the clay and the impulse exerted on the clay if it does not bounce from the wall

74 A small bouncy ball with a momentum of 8 kgmiddotms to the left approaches head-on a large door at rest The ball bounces straight back with a momentum of 6 kgmiddotms What is the change in the momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the door

75 A 007 kg tennis ball leaves a racket with a speed of 56 ms If the ball is in contact with the racket for 004 s what is the average force on the ball by the racket

76 A 0145 kg baseball reaches a speed of 36 ms when a bat strikes If the average force of 500 N was applied on the ball by the bat what is the impact time

77 A 017 kg hockey puck slows down from 54 ms to 35 ms when it slides on horizontal ice

surface Find the change in momentum of the puck

78 A 001 kg bullet is fired at 250 ms into a wooden block that is fixed The bullet emerges from the block with a speed of 120 ms What is the change in momentum of the bullet

79 A 005 kg tennis ball moves at a speed of 10 ms and is struck by a racket causing it to rebound in the opposite direction at a speed 16 ms What is the change in momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the racket

80 A 025 kg beach ball rolling at a speed of 7 ms collides with a heavy exercise ball at rest The beach ball bounces straight back with a speed of 4 ms That is the change in momentum of the beach ball What is the impulse exerted on the beach ball What is the impulse exerted on the exercise ball

81 A 016 kg hockey puck is moving on an icy horizontal surface with a speed of 5 ms A player

strikes the puck by a hockey stick after the impact the puck moves in opposite direction with a speed of 9 ms If the puck was in contact with the stick for 0005 s what is the average force on the puck by the stick

82 A constant force of 12 N acts for 5 s on a 5 kg object What is the change in objectrsquos velocity

83 A small object with a mass of 1 kg moves in a circular path with a constant speed of 5 ms

What is the change in momentum during frac12 of period one period

General Problems

84 The diagram above shows a ballistic pendulum A 10 g bullet is fired into the suspended 2 kg

block of wood and remains embedded inside it (a perfectly inelastic collision) After the impact of the bullet the block swings up to a maximum height h If the initial speed of the bullet was 35 ms

a What was the momentum of the bullet before the collision

b What was the kinetic energy of the bullet before the collision

c What was the velocity of the bullet-block system just after the collision

d What was the total kinetic energy of the bullet-block system after the collision

e What is the maximum possible potential energy of the bullet-block system when it reaches its maximum height

f What is the maximum possible height of the bullet-block system

A B

85 Two objects A and B with masses of 32 kg and 18 kg move on a frictionless horizontal surface Object A moves to the right at a constant speed of 51 ms while object B moves to the right at a constant speed 14 ms They collide and stick together (a perfectly inelastic collision)

a Determine the total momentum of the system (both objects) before the collision

b Determine the total kinetic energy of the system before the collision

c Find the speed of the two objects after the collision

d Find the total kinetic energy of the system after the collision

e Is the kinetic energy of the system conserved Explain

86 A small cube with a mass of 25 g slides along a frictionless horizontal surface at a constant speed of 18 ms until it collides with and sticks to a large wooden 35 kg block The large block is attached to the left end of a spring with a spring constant of 100 Nm as shown above

a What is the momentum of the cube before the collision

b What is the kinetic energy of the cube before the collision

c Find the speed of the combined cube and block system just after the collision

d Find the kinetic energy of the cube-block system just after the collision

e What is the maximum potential energy that can be stored in the spring due to this collision

f How far will the cube-block system move before it stops

87 A track consists of a frictionless incline plane which is a height of 05 m and a rough horizontal

section with a coefficient of kinetic friction 002 Block A whose mass is15 kg is released from the top of the incline plane slides down and collides instantaneously and inelastically with identical block B at the lowest point The two blocks move to the right through the rough section of the track until they stop

a Determine the initial potential energy of block A

b Determine the kinetic energy of block A at the lowest point just before the collision

c Find the speed of the two blocks just after the collision

d Find the kinetic energy of the two blocks just after the collision

e How far will the two blocks travel on the rough section of the track

f How much work will the friction force do during this time

88 A bullet of mass 001 kg is moving horizontally with a speed of 100 ms when it hits a block of mass 2 kg that is at rest on a horizontal surface with a coefficient of friction of 04 After the collision the bullet becomes embedded in the block

a What is the net momentum of the bullet-block system before the collision b What is the net momentum of the bullet-block system after the collision c What is the speed of the bullet-block system after the collision d Find the total energy of the bullet-block system before the collision e Find the total energy of the bullet-block system after the collision f Is the total energy conserved during the collision g Find the maximum traveled distance of the bullet-block after the collision

89 A 35 kg child moving at 5 ms jumps onto a 40 kg sled that is initially at rest on a horizontal ice surface with the coefficient of friction of 002

a Determine the total momentum of the child-sled system before the child jumps onto the sled

b Determine the total momentum of the child-sled system after the child jumps onto the sled

c Determine the velocity of the child-sled system after the child jumps onto the sled

d Determine the total energy of the child-sled system before the child jumps onto the sled

e Determine the total energy of the child-sled system after the child jumps onto the sled

f Determine the maximum horizontal distance that child-sled can go after the child jumps onto the sled

90 A 10 g piece of sticky clay moving horizontally with a speed of 12 ms strikes a pendulum bob and sticks to the bob The pendulum bob has a mass of 50 g and it is suspended from a 07 m string

a Find the momentum of the clay before the collision

b Find the momentum of the clay-bob system after the collision

c Find the velocity of the clay-bob system after the collision

d Find the kinetic energy of the clay-bob system after the collision

e Find the maximum height of the clay-bob system that they deflect after the collision

f What velocity should the clay have before the collision in order for the clay-bob system to complete one circle

91 As shown above a 035 kg cart is moving on a horizontal frictionless track with a speed of 5 ms

when it hits and sticks to a 16 kg cart initially at rest on the track The 16 kg cart is connected to one end of a massless spring with a spring constant 80 Nm

a Determine the momentum of the 035 kg cart before the collision b Determine the kinetic energy of the 035 kg cart before the collision c Determine the momentum of the carts after the collision d Determine the kinetic energy of the carts after the collision e Is the kinetic energy conserved during the collision Explain you reasoning f Determine the maximum displacement of the spring after the collision

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

71 A toy rocket achieves a velocity of 55 ms after 3 s when fired straight up If the average force exerted by the engine is 28 N what is the toyrsquos mass

72 A 15000 kg air jet accelerates from rest to 45 ms before it takes off What is the change in

momentum of the jet

73 A 0025 kg piece of clay is thrown into a wall and has a speed of 9 ms before it strikes the wall Find the change in momentum of the clay and the impulse exerted on the clay if it does not bounce from the wall

74 A small bouncy ball with a momentum of 8 kgmiddotms to the left approaches head-on a large door at rest The ball bounces straight back with a momentum of 6 kgmiddotms What is the change in the momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the door

75 A 007 kg tennis ball leaves a racket with a speed of 56 ms If the ball is in contact with the racket for 004 s what is the average force on the ball by the racket

76 A 0145 kg baseball reaches a speed of 36 ms when a bat strikes If the average force of 500 N was applied on the ball by the bat what is the impact time

77 A 017 kg hockey puck slows down from 54 ms to 35 ms when it slides on horizontal ice

surface Find the change in momentum of the puck

78 A 001 kg bullet is fired at 250 ms into a wooden block that is fixed The bullet emerges from the block with a speed of 120 ms What is the change in momentum of the bullet

79 A 005 kg tennis ball moves at a speed of 10 ms and is struck by a racket causing it to rebound in the opposite direction at a speed 16 ms What is the change in momentum of the ball What is the impulse exerted on the ball What is the impulse exerted on the racket

80 A 025 kg beach ball rolling at a speed of 7 ms collides with a heavy exercise ball at rest The beach ball bounces straight back with a speed of 4 ms That is the change in momentum of the beach ball What is the impulse exerted on the beach ball What is the impulse exerted on the exercise ball

81 A 016 kg hockey puck is moving on an icy horizontal surface with a speed of 5 ms A player

strikes the puck by a hockey stick after the impact the puck moves in opposite direction with a speed of 9 ms If the puck was in contact with the stick for 0005 s what is the average force on the puck by the stick

82 A constant force of 12 N acts for 5 s on a 5 kg object What is the change in objectrsquos velocity

83 A small object with a mass of 1 kg moves in a circular path with a constant speed of 5 ms

What is the change in momentum during frac12 of period one period

General Problems

84 The diagram above shows a ballistic pendulum A 10 g bullet is fired into the suspended 2 kg

block of wood and remains embedded inside it (a perfectly inelastic collision) After the impact of the bullet the block swings up to a maximum height h If the initial speed of the bullet was 35 ms

a What was the momentum of the bullet before the collision

b What was the kinetic energy of the bullet before the collision

c What was the velocity of the bullet-block system just after the collision

d What was the total kinetic energy of the bullet-block system after the collision

e What is the maximum possible potential energy of the bullet-block system when it reaches its maximum height

f What is the maximum possible height of the bullet-block system

A B

85 Two objects A and B with masses of 32 kg and 18 kg move on a frictionless horizontal surface Object A moves to the right at a constant speed of 51 ms while object B moves to the right at a constant speed 14 ms They collide and stick together (a perfectly inelastic collision)

a Determine the total momentum of the system (both objects) before the collision

b Determine the total kinetic energy of the system before the collision

c Find the speed of the two objects after the collision

d Find the total kinetic energy of the system after the collision

e Is the kinetic energy of the system conserved Explain

86 A small cube with a mass of 25 g slides along a frictionless horizontal surface at a constant speed of 18 ms until it collides with and sticks to a large wooden 35 kg block The large block is attached to the left end of a spring with a spring constant of 100 Nm as shown above

a What is the momentum of the cube before the collision

b What is the kinetic energy of the cube before the collision

c Find the speed of the combined cube and block system just after the collision

d Find the kinetic energy of the cube-block system just after the collision

e What is the maximum potential energy that can be stored in the spring due to this collision

f How far will the cube-block system move before it stops

87 A track consists of a frictionless incline plane which is a height of 05 m and a rough horizontal

section with a coefficient of kinetic friction 002 Block A whose mass is15 kg is released from the top of the incline plane slides down and collides instantaneously and inelastically with identical block B at the lowest point The two blocks move to the right through the rough section of the track until they stop

a Determine the initial potential energy of block A

b Determine the kinetic energy of block A at the lowest point just before the collision

c Find the speed of the two blocks just after the collision

d Find the kinetic energy of the two blocks just after the collision

e How far will the two blocks travel on the rough section of the track

f How much work will the friction force do during this time

88 A bullet of mass 001 kg is moving horizontally with a speed of 100 ms when it hits a block of mass 2 kg that is at rest on a horizontal surface with a coefficient of friction of 04 After the collision the bullet becomes embedded in the block

a What is the net momentum of the bullet-block system before the collision b What is the net momentum of the bullet-block system after the collision c What is the speed of the bullet-block system after the collision d Find the total energy of the bullet-block system before the collision e Find the total energy of the bullet-block system after the collision f Is the total energy conserved during the collision g Find the maximum traveled distance of the bullet-block after the collision

89 A 35 kg child moving at 5 ms jumps onto a 40 kg sled that is initially at rest on a horizontal ice surface with the coefficient of friction of 002

a Determine the total momentum of the child-sled system before the child jumps onto the sled

b Determine the total momentum of the child-sled system after the child jumps onto the sled

c Determine the velocity of the child-sled system after the child jumps onto the sled

d Determine the total energy of the child-sled system before the child jumps onto the sled

e Determine the total energy of the child-sled system after the child jumps onto the sled

f Determine the maximum horizontal distance that child-sled can go after the child jumps onto the sled

90 A 10 g piece of sticky clay moving horizontally with a speed of 12 ms strikes a pendulum bob and sticks to the bob The pendulum bob has a mass of 50 g and it is suspended from a 07 m string

a Find the momentum of the clay before the collision

b Find the momentum of the clay-bob system after the collision

c Find the velocity of the clay-bob system after the collision

d Find the kinetic energy of the clay-bob system after the collision

e Find the maximum height of the clay-bob system that they deflect after the collision

f What velocity should the clay have before the collision in order for the clay-bob system to complete one circle

91 As shown above a 035 kg cart is moving on a horizontal frictionless track with a speed of 5 ms

when it hits and sticks to a 16 kg cart initially at rest on the track The 16 kg cart is connected to one end of a massless spring with a spring constant 80 Nm

a Determine the momentum of the 035 kg cart before the collision b Determine the kinetic energy of the 035 kg cart before the collision c Determine the momentum of the carts after the collision d Determine the kinetic energy of the carts after the collision e Is the kinetic energy conserved during the collision Explain you reasoning f Determine the maximum displacement of the spring after the collision

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

General Problems

84 The diagram above shows a ballistic pendulum A 10 g bullet is fired into the suspended 2 kg

block of wood and remains embedded inside it (a perfectly inelastic collision) After the impact of the bullet the block swings up to a maximum height h If the initial speed of the bullet was 35 ms

a What was the momentum of the bullet before the collision

b What was the kinetic energy of the bullet before the collision

c What was the velocity of the bullet-block system just after the collision

d What was the total kinetic energy of the bullet-block system after the collision

e What is the maximum possible potential energy of the bullet-block system when it reaches its maximum height

f What is the maximum possible height of the bullet-block system

A B

85 Two objects A and B with masses of 32 kg and 18 kg move on a frictionless horizontal surface Object A moves to the right at a constant speed of 51 ms while object B moves to the right at a constant speed 14 ms They collide and stick together (a perfectly inelastic collision)

a Determine the total momentum of the system (both objects) before the collision

b Determine the total kinetic energy of the system before the collision

c Find the speed of the two objects after the collision

d Find the total kinetic energy of the system after the collision

e Is the kinetic energy of the system conserved Explain

86 A small cube with a mass of 25 g slides along a frictionless horizontal surface at a constant speed of 18 ms until it collides with and sticks to a large wooden 35 kg block The large block is attached to the left end of a spring with a spring constant of 100 Nm as shown above

a What is the momentum of the cube before the collision

b What is the kinetic energy of the cube before the collision

c Find the speed of the combined cube and block system just after the collision

d Find the kinetic energy of the cube-block system just after the collision

e What is the maximum potential energy that can be stored in the spring due to this collision

f How far will the cube-block system move before it stops

87 A track consists of a frictionless incline plane which is a height of 05 m and a rough horizontal

section with a coefficient of kinetic friction 002 Block A whose mass is15 kg is released from the top of the incline plane slides down and collides instantaneously and inelastically with identical block B at the lowest point The two blocks move to the right through the rough section of the track until they stop

a Determine the initial potential energy of block A

b Determine the kinetic energy of block A at the lowest point just before the collision

c Find the speed of the two blocks just after the collision

d Find the kinetic energy of the two blocks just after the collision

e How far will the two blocks travel on the rough section of the track

f How much work will the friction force do during this time

88 A bullet of mass 001 kg is moving horizontally with a speed of 100 ms when it hits a block of mass 2 kg that is at rest on a horizontal surface with a coefficient of friction of 04 After the collision the bullet becomes embedded in the block

a What is the net momentum of the bullet-block system before the collision b What is the net momentum of the bullet-block system after the collision c What is the speed of the bullet-block system after the collision d Find the total energy of the bullet-block system before the collision e Find the total energy of the bullet-block system after the collision f Is the total energy conserved during the collision g Find the maximum traveled distance of the bullet-block after the collision

89 A 35 kg child moving at 5 ms jumps onto a 40 kg sled that is initially at rest on a horizontal ice surface with the coefficient of friction of 002

a Determine the total momentum of the child-sled system before the child jumps onto the sled

b Determine the total momentum of the child-sled system after the child jumps onto the sled

c Determine the velocity of the child-sled system after the child jumps onto the sled

d Determine the total energy of the child-sled system before the child jumps onto the sled

e Determine the total energy of the child-sled system after the child jumps onto the sled

f Determine the maximum horizontal distance that child-sled can go after the child jumps onto the sled

90 A 10 g piece of sticky clay moving horizontally with a speed of 12 ms strikes a pendulum bob and sticks to the bob The pendulum bob has a mass of 50 g and it is suspended from a 07 m string

a Find the momentum of the clay before the collision

b Find the momentum of the clay-bob system after the collision

c Find the velocity of the clay-bob system after the collision

d Find the kinetic energy of the clay-bob system after the collision

e Find the maximum height of the clay-bob system that they deflect after the collision

f What velocity should the clay have before the collision in order for the clay-bob system to complete one circle

91 As shown above a 035 kg cart is moving on a horizontal frictionless track with a speed of 5 ms

when it hits and sticks to a 16 kg cart initially at rest on the track The 16 kg cart is connected to one end of a massless spring with a spring constant 80 Nm

a Determine the momentum of the 035 kg cart before the collision b Determine the kinetic energy of the 035 kg cart before the collision c Determine the momentum of the carts after the collision d Determine the kinetic energy of the carts after the collision e Is the kinetic energy conserved during the collision Explain you reasoning f Determine the maximum displacement of the spring after the collision

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

86 A small cube with a mass of 25 g slides along a frictionless horizontal surface at a constant speed of 18 ms until it collides with and sticks to a large wooden 35 kg block The large block is attached to the left end of a spring with a spring constant of 100 Nm as shown above

a What is the momentum of the cube before the collision

b What is the kinetic energy of the cube before the collision

c Find the speed of the combined cube and block system just after the collision

d Find the kinetic energy of the cube-block system just after the collision

e What is the maximum potential energy that can be stored in the spring due to this collision

f How far will the cube-block system move before it stops

87 A track consists of a frictionless incline plane which is a height of 05 m and a rough horizontal

section with a coefficient of kinetic friction 002 Block A whose mass is15 kg is released from the top of the incline plane slides down and collides instantaneously and inelastically with identical block B at the lowest point The two blocks move to the right through the rough section of the track until they stop

a Determine the initial potential energy of block A

b Determine the kinetic energy of block A at the lowest point just before the collision

c Find the speed of the two blocks just after the collision

d Find the kinetic energy of the two blocks just after the collision

e How far will the two blocks travel on the rough section of the track

f How much work will the friction force do during this time

88 A bullet of mass 001 kg is moving horizontally with a speed of 100 ms when it hits a block of mass 2 kg that is at rest on a horizontal surface with a coefficient of friction of 04 After the collision the bullet becomes embedded in the block

a What is the net momentum of the bullet-block system before the collision b What is the net momentum of the bullet-block system after the collision c What is the speed of the bullet-block system after the collision d Find the total energy of the bullet-block system before the collision e Find the total energy of the bullet-block system after the collision f Is the total energy conserved during the collision g Find the maximum traveled distance of the bullet-block after the collision

89 A 35 kg child moving at 5 ms jumps onto a 40 kg sled that is initially at rest on a horizontal ice surface with the coefficient of friction of 002

a Determine the total momentum of the child-sled system before the child jumps onto the sled

b Determine the total momentum of the child-sled system after the child jumps onto the sled

c Determine the velocity of the child-sled system after the child jumps onto the sled

d Determine the total energy of the child-sled system before the child jumps onto the sled

e Determine the total energy of the child-sled system after the child jumps onto the sled

f Determine the maximum horizontal distance that child-sled can go after the child jumps onto the sled

90 A 10 g piece of sticky clay moving horizontally with a speed of 12 ms strikes a pendulum bob and sticks to the bob The pendulum bob has a mass of 50 g and it is suspended from a 07 m string

a Find the momentum of the clay before the collision

b Find the momentum of the clay-bob system after the collision

c Find the velocity of the clay-bob system after the collision

d Find the kinetic energy of the clay-bob system after the collision

e Find the maximum height of the clay-bob system that they deflect after the collision

f What velocity should the clay have before the collision in order for the clay-bob system to complete one circle

91 As shown above a 035 kg cart is moving on a horizontal frictionless track with a speed of 5 ms

when it hits and sticks to a 16 kg cart initially at rest on the track The 16 kg cart is connected to one end of a massless spring with a spring constant 80 Nm

a Determine the momentum of the 035 kg cart before the collision b Determine the kinetic energy of the 035 kg cart before the collision c Determine the momentum of the carts after the collision d Determine the kinetic energy of the carts after the collision e Is the kinetic energy conserved during the collision Explain you reasoning f Determine the maximum displacement of the spring after the collision

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

f How much work will the friction force do during this time

88 A bullet of mass 001 kg is moving horizontally with a speed of 100 ms when it hits a block of mass 2 kg that is at rest on a horizontal surface with a coefficient of friction of 04 After the collision the bullet becomes embedded in the block

a What is the net momentum of the bullet-block system before the collision b What is the net momentum of the bullet-block system after the collision c What is the speed of the bullet-block system after the collision d Find the total energy of the bullet-block system before the collision e Find the total energy of the bullet-block system after the collision f Is the total energy conserved during the collision g Find the maximum traveled distance of the bullet-block after the collision

89 A 35 kg child moving at 5 ms jumps onto a 40 kg sled that is initially at rest on a horizontal ice surface with the coefficient of friction of 002

a Determine the total momentum of the child-sled system before the child jumps onto the sled

b Determine the total momentum of the child-sled system after the child jumps onto the sled

c Determine the velocity of the child-sled system after the child jumps onto the sled

d Determine the total energy of the child-sled system before the child jumps onto the sled

e Determine the total energy of the child-sled system after the child jumps onto the sled

f Determine the maximum horizontal distance that child-sled can go after the child jumps onto the sled

90 A 10 g piece of sticky clay moving horizontally with a speed of 12 ms strikes a pendulum bob and sticks to the bob The pendulum bob has a mass of 50 g and it is suspended from a 07 m string

a Find the momentum of the clay before the collision

b Find the momentum of the clay-bob system after the collision

c Find the velocity of the clay-bob system after the collision

d Find the kinetic energy of the clay-bob system after the collision

e Find the maximum height of the clay-bob system that they deflect after the collision

f What velocity should the clay have before the collision in order for the clay-bob system to complete one circle

91 As shown above a 035 kg cart is moving on a horizontal frictionless track with a speed of 5 ms

when it hits and sticks to a 16 kg cart initially at rest on the track The 16 kg cart is connected to one end of a massless spring with a spring constant 80 Nm

a Determine the momentum of the 035 kg cart before the collision b Determine the kinetic energy of the 035 kg cart before the collision c Determine the momentum of the carts after the collision d Determine the kinetic energy of the carts after the collision e Is the kinetic energy conserved during the collision Explain you reasoning f Determine the maximum displacement of the spring after the collision

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

90 A 10 g piece of sticky clay moving horizontally with a speed of 12 ms strikes a pendulum bob and sticks to the bob The pendulum bob has a mass of 50 g and it is suspended from a 07 m string

a Find the momentum of the clay before the collision

b Find the momentum of the clay-bob system after the collision

c Find the velocity of the clay-bob system after the collision

d Find the kinetic energy of the clay-bob system after the collision

e Find the maximum height of the clay-bob system that they deflect after the collision

f What velocity should the clay have before the collision in order for the clay-bob system to complete one circle

91 As shown above a 035 kg cart is moving on a horizontal frictionless track with a speed of 5 ms

when it hits and sticks to a 16 kg cart initially at rest on the track The 16 kg cart is connected to one end of a massless spring with a spring constant 80 Nm

a Determine the momentum of the 035 kg cart before the collision b Determine the kinetic energy of the 035 kg cart before the collision c Determine the momentum of the carts after the collision d Determine the kinetic energy of the carts after the collision e Is the kinetic energy conserved during the collision Explain you reasoning f Determine the maximum displacement of the spring after the collision

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

Practice Multiple Choice Questions

1 A freight car of mass 20000 kg moves along a frictionless level railroad track with a constant speed of 15 ms What is the momentum of the car A 30000 kgms

B 3000 kgms

C300000 kgms

D 3000000 kgms

E 300 kgms

2 A 500 kg sailboat moves with a momentum of 150000 kgms What is the velocity of the boat A300 ms B 3 ms C 30 ms D 3000 ms E 30000 ms

3 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

4 The momenta of two different objects are presented by on the diagram Which of the following is the net momentum of the system of two objects

A B

C D

E

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

5 A cannon fires a cannonball and recoils backward Which of the following statements is true about the cannon recoil A It happens because the energy of the system is conserved

B It happens because the energy of the system is increased

C It happens because the momentum of the system is not conserved

D It happens because the momentum of the system is conserved

E It happens because the momentum of the system is increased

6 An air balloon hovers at a certain altitude above the ground A pilot throws a sand bag down from the balloon What is the direction of the balloonrsquos velocity just after the bag was thrown

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

A B C D E

7 What is the momentum of the cannon after firing a cannon ball with an initial momentum of 5000 kgms to the right

A 5000 kgms to the right B 5000 kgms to the left C zero

D 2500 kgms to the right E 2500 kgms to the left

8 A platform moves at a constant velocity on a horizontal surface What happens to the velocity of the platform after a sudden rain falls down A It increases because the energy is conserved

B It decreases because the energy is conserved

C It remains constant because the momentum is conserved

D It increases because the momentum is conserved

E It decreases because the momentum is conserved

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

9 A stationary skateboarder I with a mass of 50 kg pushes a stationary skateboarder II with a mass of 75 kg After the push the skateboarder II moves with a velocity of 2 ms to the right What is the velocity of the skateboarder I A 3 ms to the left

B 2 ms to the left

C 1 ms to the right

D 3 ms to the right

E 2 ms to the right

10 A loaded freight car A with a mass of 24000 kg moves at a constant velocity of 8 ms on a horizontal railroad track and collides with an empty stationary car B with a mass of 8000 kg After the collision the cars stick to each other and moves like one object What is the velocity of two cars after the collision A 2 ms B 4 ms C 6 ms D 8 ms D 12 ms

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

11 A 40 kg skateboarder runs at a constant velocity of 012 ms and jumps of a stationary skateboard with a mass of 8 kg What is the velocity of the skateboard after the jump A 012 ms B 090 ms C 060 ms D 020 ms E 010 ms

12 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves at a constant velocity of 2 ms What is the velocity of the boat after the jump if the diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the boat A 2 ms B 3 ms C 4 ms D 5 ms E 6 ms

13 Block A with a mass 2m moves on a frictionless horizontal surface at a constant speed v and collides inelastically with B of mass m What is the velocity of two blocks after the collision A v B v C v D v E v

14 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block A after the collision A 0 ms B v C v D v E v

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

15 Block A with a mass m moves on a frictionless horizontal surface at a constant velocity v and collides elastically with an identical block B What is the velocity of block B after the collision A 0 ms B v C v D v E v

16 A 10 kg object moves at a constant velocity 2 ms to the right and collides with a 4 kg object moving at a velocity 5 ms to the left Which of the following statements is correct A The total momentum before and after the collision is 20 kgms

B The total momentum before and after the collision is 40 kgms

C The total momentum before and after the collision is 10 kgms

D The total momentum before and after the collision is 30 kgms

E The total momentum before and after the collision is zero

17 When two objects collide elastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is lost

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

18 When two objects collide inelastically the momentum is conserved Which of the following is true about the kinetic energy during the collision A The kinetic energy is conserved

B The kinetic energy is not conserved

C The kinetic energy is gained

D The kinetic energy completely transforms into thermal energy

E More information is required

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

19 A light beach ball moving with a velocity 2 ms to the right collides elastically with a stationary bowling ball After the collision the bowling ball remains stationary What is the velocity of the beach ball after the collision A 0 ms B 2 ms to the left C 4 ms to the left

D 3 ms to the left E 1 ms to the left

20 A bowling ball moving with a constant speed v collides elastically with a stationary beach ball After the collision the bowling ball barely slows down What is an approximate speed of the beach ball after the collision A v B v C v D 2v E 3v

21 A big truck collides inelastically with a small car Which of the following statements is true A The truck experiences the greater magnitude of impulse during the collision

B The car experiences the greater magnitude of impulse during the collision

C They experience the same magnitude of impulse during the collision

D The impulse of each object is zero during the collision

E More information is required

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

22 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back with a momentum of 6 kgms after the collision with the racket What is the change in momentum of the tennis ball A 1 kgms B 5 kgms C 6 kgms D 11 kgms E 0 kgms

23 A rubber ball moving with an initial momentum Pi collides elastically with a vertical wall Which of the following is correct about the vector of impulse that the ball experiences during the collision

A B C D E

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

24 A piece of clay moving with an initial momentum Pi collides with a vertical wall and sticks to it Which of the following is correct about the vector of impulse that the clay experiences during the collision

A B C D E

25 The force as a function of time is presented by the graph What is the impulse exerted on the object during first six seconds A 40 Ns

B 80 Ns

C 120 Ns

D 240 Ns

E 360 Ns

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m

Answers

1) 75000 kgms 2) 167 ms 3) 1200 kg 4) 24 kgms 5) 70 kg 6) 311 ms 7) 252 kgms 8) 85 kg 9) 32 ms 10) 50000 kgms 11) 3185x10-24 kgms 12) 266 kgms

13) 176 kgms 14) -20 kgms 15) 14 kgms 16) -1156 kgms 17) -1156 kgms 18) 1340 kgms

19) 158 ms 20) 133 ms 21) -465 ms 22) 729 ms 23) 233 ms 24) 2 ms 25) 28683 ms 26) -22 ms 27) 1435 ms 28) -129 ms 29) 857 ms 30) -44 ms 31) 1 ms 32) 18 ms 33) 30 ms 34) 45 ms 35) 17 ms 36) -11 ms 37) 9 ms 38) 20 ms

39) 10 ms 40) 10 ms 41) 40 mph 42) 18 ms 43) 7ms 44) -6 ms 45) -3 ms 46) -9 ms 47) 40 ms 48) 20 ms 49) 130 mph 50) V1f = 46 ms

V2f = 316 ms 51) V1f = 4454 ms

V2f = 5253 ms 52) V1f = -607 ms

V2f = 62475 ms 53) V1f = -536 ms

V2f = 2791 ms 54) V1f = 45 ms

V2f = 195 ms 55) V1f = -111 ms

V2f = 249 ms 56) ∆p=4800 kgms

57) ∆psmall = 11 kgms Ismall = 11 kgms Ilarge = -11 kgms

58) 340 N 59) 1527 kg 60) 675000 kgms 61) ∆p = -225 kgms

∆I = -225 kgms 62) ∆p = 14 kgms

IB = 14 kgms Idoor = -14 kgms

63) 98 N 64) 01044 s 65) -323 kgms 66) -13 kgms 67) ∆p = -13 kgms

Iball = -13 kgms Iracket = 13 kgms

68) ∆p = -275 kgms IBB = -275kgms

IEB = 275kgms 69) -448 N 70) 12 ms

71) ∆p12 period = -10 kgms ∆p1 period = 0

72) a) 35 Kgms b) 6125 J c) 17 ms d) 03 J e) 03 J f) 0015 m

73) a) 1884 kgms

b) 434 J c) 3768 ms d) 355 J e) No

74) a) 45 kgms b)405 J c)128 ms d)0289 J e)0289 J f) 074m

75) a) 735 J b) 735 J c) 157 ms d) 37 J e) 625 m f) 3675 J

76) a) 1 kgms b) 1 kgms c) 05 ms d) 50 J e) 025 J f) No g) 003 m

77) a) 175 kgms b) 175 kgms c) 233 ms d) 4375 J e) 203584 J f) 1384 m

78) a) 012 kgms b) 012 kgms c) 2 ms d) 012 J e) 02 m f) 264 ms

79) a) 175 kgms b) 4375 J c) 897 kgms d) 078 J e) No f) 014 m