Chapter 06 Test A. Name: Class: Date: Multiple Choice Identify the choice that best completes the statement or answers the question.

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1 Name: Class: Date: Chapter 06 Test A Multiple Choice Identify the choice that best completes the statement or answers the question. 1. The property of matter that resists changes in motion is: a. acceleration. b. inertia. c. force. d. speed. 2. As the mass of an object is increased, what happens to its inertia? a. It increases b. It decreases c. It stays the same d. Inertia and mass are not related in any way Figure 6-1A 3. If each of the barbells in Figure 6-1A were pushed with a force of 100 newtons, which would be harder to move? a. The 10-kg barbell b. The 20-kg barbell c. The 30-kg barbell d. They would all move equally 4. A ball is rolling down a level sidewalk. As it rolls along, it slows down and stops. Why? a. Continued motion requires a force. b. Frictional force acts on the ball to stop it. c. The net force on a moving ball is always zero. d. The force that started it moving was taken away. 5. An object moving with constant speed has: a. a net force greater than zero. b. a net force equal to zero. c. a net force less than zero. d. an unbalanced net force. 1

2 Name: 6. Changes in motion come from: a. unbalanced forces. b. balanced forces. c. mass. d. inertia. 7. A 0.15-kilogram baseball and a 7.25-kilogram bowling ball are both rolling along at 3 m/s. Which object is easier to stop and why? a. The bowling ball because it has less inertia b. The baseball because it has more inertia c. The bowling ball because heavy objects are naturally prone to stop on their own d. The baseball because it has less inertia A skater is gliding across the ice. Four forces act upon him as shown in the illustration below. Force F A is 40 newtons, Force F C is 40 newtons and Force F B is 500 newtons. Using the illustration and the information above, answer the following: Figure 6-2A 8. The skater in Figure 6-2A is given an additional 50 N push forward. The friction force of the ice does not change. What is the net force on him? a. zero b. 50 N c. 250 N d. 500 N 9. A ball with a mass of 1 kg is moving in a straight line at the same speed as a ball with a mass of 10 kg. Both balls are brought to rest in 4.0 seconds. What is true of the force required to stop the balls? a. It takes less force to stop the 1 kilogram ball because it has less inertia. b. It takes more force to stop the 1 kilogram ball because it has more inertia. c. It takes the same force to stop both balls because they moving at the same speed. d. It takes less force to stop the 10 kilogram ball because it has less inertia. 10. An object at rest has: a. both inertia and momentum. b. neither inertia nor momentum. c. momentum but no inertia. d. inertia but no momentum. 2

3 Name: 11. Cheung pushes on a toy car, and it accelerates at 0.22 meters per second per minute. Carlos pushes on the same toy car with twice as much force as Cheung. Compare the acceleration when Carlos pushes the car to when Cheung pushes the car. a. The acceleration is 1/4 as much. b. The acceleration is 1/2 as much. c. The acceleration is twice as much. d. The acceleration is the same. 12. A 20-kg dog on ice skates is accelerating at 2 m/s 2. What is the net force on the dog? a. 2 N b. 10 N c. 22 N d. 40 N 13. Tessa uses a toy slingshot to launch a tennis ball across the park for her dog to fetch. For her first launch, she uses 50 N of force. Her second launch uses 100 N of force, and her third launch uses 150 N. Which launch had the greatest acceleration of the tennis ball? a. The 50-N launch b. The 100-N launch c. The 150-N launch d. They all had the same acceleration. In the graph below, the acceleration of an object is plotted against the net force applied to the object. Figure 6-3A 14. When a net force of 2 newtons is applied, the object graphed in Figure 6-3A accelerates at: a. 1 m/s 2 b. 2 m/s 2 c. 3 m/s 2 d. 4 m/s The mass of the object being accelerated in Figure 6-3A is: a. 0.2 kg b. 0.5 kg c. 1 kg d. 2 kg 3

4 Name: 16. A tennis player hits a 60-gram tennis ball with a force of 3 newtons. The ball accelerates at a rate of: a m/s 2 b. 20 m/s 2 c. 50 m/s 2 d. 180 m/s A book rests on a table. The force of gravity pulls down on the book with a force of 20 newtons. What prevents the book from accelerating downward at 9.8 m/s 2? a. The table presses back up on the book with an equal and opposite force of 20 newtons. b. The table presses back up on the book with a force greater than 20 newtons. c. The table and the book together are accelerating downwards at 9.8 m/s 2. d. The inertia of the book holds it up. 18. A rocket can fly into space because: a. when it is launched, the hot exhaust gases hit the ground and push the rocket forward. b. the rocket pushes the exhaust gases backward, and there is an equal and opposite reaction pushing the rocket forward. c. when the gases are burning up, the mass of the rocket decreases, changing the amount of gravity on the rocket. d. the launch pad pushes the rocket forward like a slingshot. 19. Every action force creates a reaction force that is equal in strength and opposite in direction. This statement summarizes Newton s: a. 1st law of motion. b. 2nd law of motion. c. 3rd law of motion. d. law of gravitational force. 20. The momentum of an object depends on what two factors? a. Force and acceleration b. Mass and acceleration c. Force and velocity d. Mass and velocity 21. What is the momentum of a 0.15-kilogram baseball moving at 20 m/s? a. 1.5 kg m/s b. 3 kg m/s c. 15 kg m/s d. 30 kg m/s 22. A kayaker paddles a boat through the water. Which of the following are an action/reaction pair in this situation? a. The force of the water pushing on the paddle and the force of the paddle pushing on the water. b. The force of the paddle pushing on the water and the force of the kayak pushing through the water. c. The force of the water pushing on the paddle and the force of her hand pushing on the paddle. d. The force of her hand pushing on the paddle and the force of the kayak pushing through the water. 4

5 Name: 23. A force of 50 newtons is exerted by a bat on a baseball. The force exerted by the baseball on the bat is: a. less than 50 newtons. b. 50 newtons. c. more than 50 newtons. d. Cannot be determined from the data Kyela and her brother are roller skating and collide. Kyela has a mass of 60 kg and her brother has a mass of 30 kg. Answer the following questions based on the illustration. Figure 6-4A 24. After Kyela collides with her brother as shown in Figure 6-4A, how do their accelerations compare? a. Kyela accelerates faster than her brother. b. Her brother accelerates faster than Kyela. c. They both have the same acceleration. d. Neither will accelerate, because they are traveling at constant velocity. 25. After Kyela collides with her brother in Figure 6-4A, how do their momentums compare? a. Kyela has a higher momentum. b. Her brother has a higher momentum. c. Kyela and her brother have the same momentum. d. Neither has any momentum. 26. The equation to calculate momentum is: a. mass inertia b. mass velocity c. mass velocity d. mass acceleration 27. You stand on a skateboard and push off the ground with one of your feet. How does the force applied by your foot to the ground compare to the force applied by the ground to your foot? a. They are equal. b. The force applied by your foot to the ground is larger. c. The force applied by the ground to your foot is larger. d. They cannot be compared. 28. What is the momentum of a 2000-kg car traveling at 20 m/s? a. 0 kg m/s b kg m/s c. 100 kg m/s d. 40,000 kg m/s 5

6 Name: 29. A 10,000-kg rocket is traveling from its launch pad at a speed of 100 m/s. At what speed would 1000 kg of gases be expelled from the rocket? a. 10 m/s b. 100 m/s c m/s d. 10,000 m/s 30. A 2-kg piece of clay moving at 4 m/s strikes and sticks to a second 4-kg piece of clay moving at 1 m/s in the opposite direction. What is the speed of the combined piece of clay? a m/s b. 2 m/s c. 4 m/s d. 6 m/s 6