Acceleration/Free Fall

1. A ball isthrown vertically upward.a. What happens to the ball's velocitywhile the ball is in the air? , ÿ ÿ os,, ,'ÿ

b. What is its velocity when it reaches'Its maximum altitude?

c. What is its acceleration when it reaches its maximum altitude?--q .%

d. Does its acceleration increase, decrease, or remain constant?

2. A cross-country runner runs 5.0 km east along the course, then turns around and runs 5.0 km

west along the same path. She returns to the starting point in 40 minutes.a. What is her average speed?

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b. What is her average velocity?

° Sketch the velocity-time graph for the following motions.a. A city bus that is moving with a constant velocity.

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b. A wheelbarrow that is speeding up at a uniform rate of speed while moving in the positivedirection

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+A tiger that is speeding up at a uniform rate of speed while moving in the negative direction.

d. An iguana that is slowing down at a uniform rate of speed while moving in the positive direction

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Acceleration/Free Fall

4. A car traveling in a straight line has a velocity of +5.0 m/s. After an acceleration of 0.75 m/s/s, the car's

velocity is 8.0 m/s. In what time interval did the acceleration occur?

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5. A car traveling at 7.0 m/s accelerates at the rate of 0.8 m/s/s. How fast is it going after 2.0 s?

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6. A snowmobile has an initial velocity of +3 m/s.a. If it accelerates at the rate of 0.5 m/s/s for 7.0 s, what is the final velocity?

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b. If it accelerates at the rate of-0.6 m/s/s, how long will it take to reach a complete stop?

7. A car moving westward along a straight, level road increases its velocity uniformly from 16 m/s to 32

m/s in 10.0 s.a. What is the car's acceleration?

b. What is its average velocity?_.r

c. How far did it move while accelerating?

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Acceleration/Free Fall

8. A ball initially at rest rolls down a hill with an acceleration of 3.3 m/s/s. If it accelerates for 7.5 s, howfar will it move?

9. A bus slow sown uniformly from 75.0 km/h to 0 km/h in 21 s. How far does it travel before stopping?

10. A car accelerates from rest at-3.00 m/s/s.a. What is the velocity at the end of 5.0 s?

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b. What is the displacement after 5.0 s?

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C, Sketch a displacement-time graph of this motion.

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Acceleration/Free Fall

11. An elevator is moving upward 1.20 m/s when it experiences an acceleration of 0.31 m/s/s downward,over a distance of 0.75 m. What will its final velocity be?

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12. A worker drops a wrench from the top of a tower 80.0 m tall (on earth). What is the velocity when thewrench strikes the ground?

13. If the avera ÿe vel " of an object is the same for all time intervals, then the object moves at a(n)

z lÿ!Lyÿa Constant velo Citvelocityÿ

c. Changing speedd. Relative speed

14. Instead ofÿ ÿro_p_ped,-a-balMs-lhrown down. Which of the following statements are not true.

_ÿa.Jÿ .... Thee acceieration is greater than-9.8-m-ÿs2ÿ-5ÿ

,ÿ'c.ÿ ......... The acceleration ÿ S'iÿoÿg]i-ffÿ..... aT .......... Tiÿ-dlÿpl3cemenÿ ÿs" negatlve-'ÿ-" .

15. Ignoring air resistance, if a 10-kg ball and a 200 kg crate were both dropped from the top of the SearsTower, the acceleration of the crate would be the acceleration of the ball.

a. Greater thanb. Less than

,jcÿ ...... Equal_£oÿ_2:::

16. A toy rocket is launched straight up into the air. When the rocket reaches its maximum height, itsvelocity isa. At it maximum

c. Equal to its displacement multiplied by timed. Equal to its displacement divided by time

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