1

NEWTON’S LAWS OF MOTION

Newton’s 1st Law of Motion(The Law of Inertia)

The law states:An object at __________ remains at __________, and an object in __________ remains in __________ with the same __________and __________ unless acted upon by an __________ force.

2

Objects want to do what they are doing…..

if it is in motion, it wants to stay in motion; OR if it is not moving, is doesn’t want to move…….

the only thing that changes the motion of the object is an _________________________

What Does the Law Really Mean?

InertiaThe __________ of an object to change its __________ or the direction of its __________Inertia is related to mass….the __________ the mass of the object, the __________ it is to change the motion of the object

Newton’s 1st Law of Motion(The Law of Inertia)

3

Newton’s 2nd Law of Motion

The law states:__________ causes an object to __________, while the object’s __________ resists __________.

What does the law really mean?

__________ increases with more force and decreases with more __________

__________ is in the __________direction as the force

4

Calculating Force

Force = mass x acceleration

force is measured in __________

Can also calculate for mass and acceleration

newton

Force is measured in newtons

__________ newton = the amount of force needed to accelerate 1 kg of mass 1 m/s2

1 N = 1 kg x m/s2

5

Calculating Force pg 51

F = ma

Calculating Acceleration pg 52

a = F/m

6

m = F/a

Calculating Mass pg 53

Centripetal Force

Centripetal force is any force that keeps an object moving in a __________

The force points toward the __________ of the circle

Without centripetal force an object would go flying in a __________ __________

7

Can use F = ma on circular motion

greater acceleration needs greater centripetal force

the greater mass, the more centripetal force is needed to have the same speed as an object with less mass

Centripetal Force (cont)

8

The law states:If one object exerts a force on another object, then the second object exerts a __________ that is __________ in size and __________ in __________ back on the

__________ object.

Newton’s 3rd Law of Motion

For every __________ there is an __________and __________ reaction

What does the law really mean?

9

Action-Reaction Pairs

The force that is exerted on an object and the force that the object exerts back, together are called action – reaction pairs

___________________________

Action-Reaction Pairs -Examples

_______________________________

Action:

Reaction:

Result:

____________________________

10

Action-Reaction Pairs -Examples

Action – _________________________

Reaction – ______ _______________ Result – ________

___________________

Action/Reaction Pairs

What is the reaction to the action shown?

11

Balanced Forces vs. Action/Reaction Pairs

Balanced Forces2 equal forces that act in an __________ direction on 1 object… the forces __________ each other out

Action/Reaction Forces2 equal forces that do not cancel each other out because the forces act on __________ objects

Balanced Force or Action/Reaction Pair?

12

Balanced Force or Action/Reaction Pair?

If you are pushing on something, it pushes back on you the __________ amount.

When you lean against your friend, you both feel the same sized force and the force each of you feels is acting in

opposite directions.

Newton’s 3 Laws Work Together

13

1st Law – _________________________________________________________________

2nd Law – ________________________________________________________________

3rd Law – ______________________________________________________________________________________________________

Newton’s 3 Laws Work Together

Momentum

Momentum is the measure of mass in __________The momentum of an object depends in its __________ and __________Momentum is a __________

14

Forces Transfer Momentum

Momentum is __________ from one object to another

Calculating Momentum

momentum = mass x velocity

Unit of momentum – kg·m/s

15

Calculating Momentum

What is the momentum of a 1.5 kg ball moving at 2 m/s?

A 3 kg ball is moving with a velocity of 1 m/s? What is the ball’s momentum?