AP Physics Chapter 2 Practice Test Answers: E,E,A,E,C,D,E,A,C,B,D,C,A,A 15. (c) 0.5 m/s 2, (d) 0.98 s, 0.49 m/s 16. (a) 48.3 m (b) 3.52 s (c) 6.4 m (d) 79.1 m 1. A 2.5 kg ball is thrown up with an initial velocity of +28.0 m/s. What is it's acceleration at the highest point? A. -2.85 m/s 2. B. 0.0 m/s 2. C. -11.2 m/s 2. D. -40.0 m/s 2. E. -9.8 m/s 2. 2. A car traveling at 20 m/s applies the brakes to produce an acceleration of -5.0 m/s/s. How far does it travel before it stops? A. 62.5 m. B. 4.0 m. C. 10.0 m. D. 80.0 m. E. 40.0 m. 3. A bus increases its speed at a constant rate from 20 m/s to 30 m/s in 10 seconds. How far does it travel in this 10 seconds? A. 250.0 m. B. 375.0 m. C. 300.0 m. D. 450.0 m. E. 200.0 m. 4. A skier slows down to 3 m/s in 8 seconds. If he traveled 112 m during this time, what was his initial speed? A. 14.0 m/s. B. 18.0 m/s. C. 20.0 m/s. D. 16.0 m/s. E. 25.0 m/s. 5. A motorcycle traveling at 10 m/s accelerates at 8 m/s/s for 4 seconds. What is the distance traveled in the 4 seconds? A. 96.0 m. B. 40.0 m. C. 104.0 m. D. 24.0 m. E. 64.0 m. 1
6. A jet takes off from a runway after traveling 800m. If it's takeoff speed is 90 m/s and it started from rest, what was it's acceleration? A. 4.0 m/s/s. B. 4.4 m/s/s. C. 4.8 m/s/s. D. 5.1 m/s/s. E. 5.6 m/s/s. 7. A rock is dropped from a 50.0 m high cliff. How long does it take it to travel the last 20 meters? A. 1.04 s. B. 2.02 s. C. 2.47 s. D. 3.19 s. E. 0.72 s. 8. A woman runs 700 m with an average speed of 4 m/s and then 300 m with an average speed of 8 m/s. What is her average speed for the entire run? A. 4.7 m/s. B. 6.0 m/s. C. 5.0 m/s. D. 5.7 m/s. E. 7.0 m/s. 9. A softball is tossed up vertically at 8 m/s, 15 m above the bottom of a well. How much time until it reaches the bottom of the well? A. 0.48 s. B. 2.11 s. C. 2.75 s. D. 1.83 s. E. 3.10 s. 10. How far did the runner whose Velocity Vs Time graph is shown below travel in the 4.0 s? A. 8.0 m. B. 10.0 m. C. 12.0 m. D. 16.0 m. E. 20.0 m. 2
11. Use the Velocity Vs Time graph above to determine the acceleration at t = 3 sec. A. 0.5 m/s 2. B. -0.5 m/s 2. C. 2.0 m/s 2. D. -2.0 m/s 2. E. -4.0 m/s 2. 12. What is the velocity of the object whose motion is graphed below at t = 3 seconds? A. 3 m/s. B. -2 m/s. C. -3 m/s. D. 2 m/s. E. -0.5 m/s. 13. At time t = 0, car X traveling with speed v 0 passes car Y. which is just starting to move. Both cars then travel on two parallel lanes of the same straight road. The graphs of speed v versus time t for both cars are shown below. Which of the following is true at time t = 20 seconds? A. Car Y is behind car X. B. Car Y is passing car X. C. Car Y is in front of car X. D. Both cars have the same acceleration. E. Car X is accelerating fester then car Y. 14. In the absence of air friction, an object dropped near the surface of the Earth experiences a constant acceleration of about 9.8 m/s 2. This means that the A. speed of the object increases 9.8 m/s during each second B. speed of the object as it falls is 9.8 m/s C. object falls 9.8 meters during each second D. object falls 9.8 meters during the first second only E. slope of the distance Vs time graph for the object equals 9.8 m/s 2 3
15. (8 Points) An astronaut drops a small snowball from a step on his spaceship on Pluto. A picture of the snowball s entire fall is taken while a strobe light flashes every 0.2 seconds. The picture showing the position of the snowball every 0.2 seconds at right is to actual scale. (a) Using a ruler, complete the position Vs Time data table below. Record your data in the units given. Time Position Position (sec) (cm) (m) 0.0 0.2 0.4 0.6 0.8 (b) Using your position Vs time data, complete the Velocity Vs Time data table below. Record your data in the units given. Use this data to construct a Velocity Vs Time graph on the axes at the bottom of the page. ΔPosition ΔTime Velocity (m) (sec) (m/s) (c) Using your Velocity Vs Time graph, determine the acceleration of the snowball. Show your work on the graph and record your answer below. Acceleration = m/s 2 (d) Using the acceleration you determined in part (c), predict the time it will take the snowball to hit the ground and its speed just before it hits. 4
16. (8 Points) Two hot air balloons are in a race and are moving vertically, balloon A is directly above balloon B as shown below. When the top of balloon B is 30 m above the ground and descending at 5 m/s, balloon A is ascending at 8 m/s. At this moment balloon A drops a spear to puncture balloon B so they can win the race. The spear is 15 m above the top of balloon B when it is released from rest, even with the bottom of balloon A. Each balloon is 6 m tall. Answer the questions below. (Note: This is a hard problem, if you can do half of it correctly you are doing well!) A 6 m (a) What is the maximum height above the ground reached by the spear? 15 m B (b) How much time passes after the spear is released to when it hits balloon B? 30 m (c) How high is the basket of balloon B when the spear punctures it? (d) How high is the basket of balloon A the moment balloon B hits the ground? Assume balloon B is in freefall the moment it is punctured. 5