Momentum

9.In a closed system, what is the total momentum before a collision compared to after?

10.A 990 kg car moving at 10 m/s collides with a stationary 4200 kg van and they stick together. What is their combined velocity immediately after?

11.A 0.058 kg tennis ball moving at 30 m/s is struck and returns at 20 m/s in the opposite direction. What is the impulse on the ball? (Take initial direction as positive.)

12.A 0.05 kg golf ball is initially at rest. It is hit by a 0.5 kg putter moving at 0.2 m/s. After the hit, the putter stops. What is the velocity of the ball?

13.A 0.06 kg tennis ball moving at 75 m/s has the same momentum as a 3 kg brick moving at 1.5 m/s. Which statement about the forces they would exert on impact is correct?

14.In a collision between two objects in a closed system, the total momentum before the collision is 12 kg m/s to the right. After the collision, one object has a momentum of 5 kg m/s to the left. What is the momentum of the other object?

15.A tennis ball of mass 0.058 kg approaches a racket horizontally at 30 m/s to the left. It is hit and returns at 20 m/s to the right. What is the magnitude of the impulse exerted on the ball?

16.A ball hits a wall and bounces back. Which of the following best explains why the ball exerts a force on the wall?

17.For a collision in which the force on a ball varies with time, what does the area under a force-time graph represent?

18.Which of the following is a vector quantity?

19.In an experiment to investigate conservation of momentum, two trolleys are placed on a frictionless track. Trolley A (mass 1.2 kg) moves at 0.5 m/s towards stationary trolley B (mass 0.8 kg). They collide and stick together. Which of the following describes the velocity of the combined trolleys after the collision?

20.A student measures the force on a ball during a collision using a force sensor. The force increases from 0 to a maximum and then decreases back to 0 over 0.02 s. The maximum force recorded is 150 N. Which of the following is the best estimate of the impulse on the ball?

21.In a laboratory experiment, a ball of mass 0.20 kg is dropped from a height onto a force sensor. It hits the sensor with speed 4.0 m/s and rebounds with speed 3.0 m/s. The contact time is 0.05 s. What is the average force exerted on the ball by the sensor?

22.Which of the following is a correct definition of impulse?

23.Two identical balls are dropped from the same height onto a hard floor. Ball A bounces back to nearly its original height, while ball B does not bounce. Which statement about the impulse on each ball from the floor is correct?

24.A student sets up an experiment to verify the conservation of momentum. Two trolleys of different masses are placed on a frictionless track. One trolley is pushed towards the other. After collision, the trolleys move together. Which measurement is NOT necessary to determine the velocity after collision?

25.The principle of conservation of momentum applies only when:

26.A force sensor records the force on a ball as a function of time during a collision, producing a force-time graph. Which quantity is obtained from the area under that graph?

27.A 0.50 kg ball moving at 2.0 m/s collides head-on with a stationary 1.0 kg ball. After the collision, the 0.50 kg ball moves backward at 0.5 m/s. What is the velocity of the 1.0 kg ball after the collision?

28.A student investigates the force exerted by a wall on a ball. The ball hits the wall perpendicularly and bounces back. Which of the following correctly describes the direction of the force on the ball?

29.A 4.0 kg trolley moving at 2.0 m/s collides with a stationary 8.0 kg trolley and they stick together. What is the velocity of the combined trolleys immediately after the collision?

30.In a closed system, the total momentum before an event is equal to the total momentum after the event. This is known as:

31.A 0.025 kg squash ball hits a wall at 44 m/s and rebounds at 42 m/s. The ball is in contact with the wall for 0.1 s. What is the force exerted on the ball by the wall? (Take initial direction as positive.)

32.A tennis ball hits a racket twice with the same change in momentum of 0.5 kg m/s. The first contact time is 2 s and the second is 0.1 s. Which hit experiences the greater force?

33.What is the correct formula for momentum?

34.An object at rest has zero momentum.

35.Which of the following statements about momentum are correct? (Select all that apply)

36.In a closed system, the total momentum before a collision equals the total momentum after the collision.

37.Impulse is equal to the change in momentum of an object.

38.What are the units of impulse?

39.Force can be defined as the rate of change of momentum.

40.Match each quantity with its correct SI unit.

41.Complete the sentence using the correct word.

42.A 0.060 kg tennis ball moving at 75 m/s has the same momentum as a 3.0 kg brick moving at 1.5 m/s. What is the momentum of the tennis ball?

43.A 0.060 kg tennis ball moving at 75 m/s has the same momentum as a 3.0 kg brick moving at 1.5 m/s. What is the momentum of the tennis ball?