Physics Study Guide: Angular Motion
Solve the following problems.
1. A cannon shot a cannon ball horizontally from the top of a cliff at 47 m/s. The cliff is 178 m high.
a. How long does it take the ball to reach the bottom?
b. How far from the base does it land?
2. A baseball player hits a baseball with a bat at 87o. The ball travels at 23 m/s.
a. Find the “hang time,” of the ball in the air.
b. Find the distance the ball travels before it hits the ground.
c. Find its maximum height.
3. A rubber stopper with a mass of .078kg is swung around on a string that is .87m long. It takes 1.2 s to complete one revolution.
a. Find the stopper’s velocity.
b. Find the stopper’s centripetal acceleration.
c. Find the centripetal force acting on the stopper.
4. Bob and Jane are on the playground together playing one day. Bob and Jane decide that they want to play on the seesaw. Jane weighs 98 kg and is 2.5 m from the pivot point. Bob weighs 176 kg. How far from the pivot does Bob need to be in order for them to have fun playing on the seesaw?
5. What is the length of a simple pendulum found on Earth whose period is 1 s?
6. What is the period of a simple pendulum found on Earth whose length is .75m?
7. There is a simple pendulum with a length of 2.5 m. It also has a period of 36s. What is the gravity where the pendulum is located?
8. What is the frequency of the pendulum in problem number 8?
9. A soccer player kicks a soccer ball from ground level with a velocity of 30 m/s at an angle of 27o above the horizontal. Find
a. its “hang time,” that is, the time the ball is in the air.
b. The distance the ball travels before it hits the ground.
c. Its maximum height
10. A stone is thrown horizontally at a speed of 12 m/s from the top of a cliff 84 m high.
a. How long does it take the stone to reach the bottom of the cliff?
b. How far from the base of the cliff does the stone strike the ground?
11. A cannon shot a cannon ball horizontally from the top of a cliff at 43 m/s. The cliff is 323 m high.
a. How long does it take the ball to reach the bottom?
b. How far from the base does it land?
12. A baseball player hits a baseball with a bat at 39o. The ball travels at 22 m/s.
a. Find the “hang time,” of the ball in the air.
b. Find the distance the ball travels before it hits the ground.
c. Find its maximum height.
13. A rubber stopper with a mass of .072 kg is swung around on a string that is 2.17m long. It takes 0.57 s to complete one revolution.
a. Find the stopper’s velocity.
b. Find the stopper’s centripetal acceleration.
c. Find the centripetal force acting on the stopper.
14. Bob and Jane are on the playground together playing one day. Bob and Jane decide that they want to play on the seesaw. Bob weighs 118 kg and is 3.5 m from the pivot point. Jane weighs 153 kg. How far from the pivot does Jane need to be in order for them to have fun playing on the seesaw?
15. Name three occupations where understanding centripetal force is important.
Key
1. a. 6.03s
b. 283.41m
2. a. 4.69s
b. 5.63m
c. 26.92m
3. a. 4.56 m/s
b. 23.85 m/s2
c. 1.86 N
4. 1.39m
5. 0.25m
6. 1.74s
7. 0.076 m/s2
8. 0.57s-1
9. a. 2.78s
b. 74.3m
c. 9.46m
10. a. 4.14s
b. 49.68m
11. a. 8.12s
b. 349.16m
12. a. 2.83s
b. 48.36m
c. 9.79m
13. a. 23.92m/s
b. 263.68 m/s2
c. 18.98N
14. 2.69m