1.) A car speeds up from 11.8 m/s, north to 32.7 m/s, north during a 15.75 second period.

What is its average velocity? What is its average acceleration? Help

2.) A car slows down from 25.6 m/s, west, to a stop, then speeds up to 18.9 m/s, east in 56 seconds.

What is its average acceleration? Help

3.) During which time interval(s): Help a) is velocity constant? b) is acceleration positive? c) is acceleration negative? |
Find the acceleration: d) between 0 and 10 s e) between 10 and 20 s f) between 20 and 30 s |

4.) A bike slows down from 14.3 m/s, west to a complete stop. Her acceleration was 4.8 m/s, east.

How much time was required to do this? Help

5.) A cat accelerates at 2.92 m/s^{2}, south for 5.7 s. Find her change in velocity. H

6.) Find the final velocity of a car that has an initial velocity of 17.1 m/s, west

after it accelerates at 3.22 m/s^{2}, east for 9.0 s. H

7.) A bus traveling at 30 km/h, south accelerates at 3.5 m/s^{2}, south for 6.8 s.

What is its final velocity in m/s? H

8.) A golf ball rolls up a green toward the hole. It starts at +2.0 m/s and accelerates at -0.5 m/s^{2}.

a) What is its velocity after 2.0 s? H

b) At what time is the ball moving at -1.0 m/s?

c) Describe, in words, the motion of the golf ball.

9.) After leaving your hand a dart accelerates at -7.92 m/s^{2} for 0.63 s until it hits a board going 8.7 m/s.

What was its velocity when it left your hand? H

10.) After 4.7 s of accelerating at 9.80 m/s^{2}, downward a rock is traveling at 36.3 m/s, downward.

What was its initial velocity? H

11.) A van traveling 85 km/h, north is at a point 82.4 m, south of a highway exit.

At a point 124.5 m, north of the same exit, his velocity is 117 km/h, north.

Assuming constant acceleration, how long did this take? H

12.) A race car traveling at 44 m/s, east is uniformly accelerated to a velocity of 22 m/s, east

in exactly 9 s. What is its displacement during this time? H

13.) From a complete stop, a runner uniformly accelerates to a point 68 m, north

of the starting point in 14.3 s. What was the runners final velocity? H

14.) A bike rider accelerates constantly to a point 9.0 m, west of a crosswalk in 4.5 s.

His velocity at that point is 7.5 m/s, west. The timer started when he was 10.0 m, east

of the crosswalk. Find his acceleration. H

15.) What is the displacement of a motorcycle that is constantly accelerating at 5.13 m/s^{2}, south

if it has an initial velocity of 4.3 m/s, south and it travels for 6.21 seconds? H

16.) An airplane starts from rest and accelerates at a constant + 3.00 m/s^{2} for 30 s before taking off.

What is the minimum length necessary for the runway? H

17.) Starting from rest, a race car moves 110 m, west in the first 5.0 s of uniform acceleration.

What is the car's accleration? H

18.) A driver brings a car from 28.6 m/s, west to a full stop in 3.1 s.

a) What is the car's accleration?

b) Find the displacement during this time. H

19.) Find the displacement for the golf ball in part a and b of problem #8 above.

b) What do you notice about these two answers?

c) How could this be? H

20.) An airplane accelerates from a velocity of 21.0 m/s, east at the constant rate of 3.0 m/s^{2}, east

over a displacement of 535 m, east. What is its final velocity? H

21.) The pilot stops the same plane in 484 m using a constant acceleration of 8.0 m/s^{2}, west.

What was the plane's velocity before braking began? H

22.) Wearing a proper seat belt you can survive a car crash if the acceleration is less than 300 m/s^{2}.

How far must the front end of the car collapse if it crashes while going 101 km/h? H

23.) Just before the cord starts to get tight, a bungee jumper is falling at 75 km/h, downward.

Soon afterward, she is traveling at 65 km/h, upward at a point 7.0 m lower than where

the cord got tight. Find her acceleration assuming it was uniform. H

24.) A brick falls freely from the top of a tall building.

a) What is its velocity after 4.0 seconds?

b) How far does it fall during that time? H

25.) You throw a rock straight upward. After 1.75 seconds it reaches its apex (highest point).

a) What was its velocity leaving your hand in km/h?

b) How high is it at its apex? H

26.) A fighter jet can accelerate at 3.57 g's. What is its acceleration? H

27.) On wet pavement, a truck can accelerate at 0.20 g's before the tires start to spin. H

a) Starting from rest, how fast is it moving (in km/h) after 17.5 s?

b) How far does it move during that time?

28.) A driver of a car going 90.0 km/h, south suddenly sees a barrier 40.0 m ahead.

It takes the driver 0.75 s before he gets his foot on the brake. If the average

acceleration during braking is 10.00 m/s^{2}, north, determine if he hits the barrier. H

29.) A driver of a truck going 112.0 km/h, north suddenly sees a barrier 77.0 m ahead.

It takes the driver 0.450 s before she gets her foot on the brake. If the average

acceleration during braking is 8.00 m/s^{2}, south, determine if she hits the barrier. H

30.) What is the maximum velocity the car in prob.#28 can have and not hit the barrier? H

31.) What is the maximum velocity the car in prob.#29 can have and not hit the barrier? H

32.) A motorcycle at rest starts to accelerate at 5.13 m/s^{2}, east just as

a car going at a constant velocity of 95.0 km/h, east passes it. H

a) At what position will the motorcycle catch the car?

b) Find the motorcycle's velocity **(in km/h)** at that position.

c) Will both vehicles have the same velocity at that position?

33.) A hare at rest starts to accelerate at 0.52 m/s^{2}, west just as

a tortoise going at a constant velocity of 2.1 m/s, west passes it. H

a) At what position will the hare catch the tortoise?

b) Find the hare's velocity at that position.

c) Will both animals have the same velocity at that position?

34.) A coin is dropped from a hot air balloon that is ascending at 1.78 m/s.

The ball hits the ground 3.97 s later.

a) After exactly one second of falling, what is the bag's velocity?

b) Find the highest position the object reached. H

35.) A marble is dropped from a rocket that is ascending at 12.8 m/s.

The ball hits the ground 14.2 s later.

a) After exactly one second of falling, what is the bag's velocity?

b) Find the highest position the object reached. H

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