1 / 39

# Momentum

Momentum. Which object has the greatest momentum? (A) a 5.00-kg mass moving at 10.0 m/s (B) a 10.0-kg mass moving at 1.00 m/s (C) a 15.0-kg mass moving at 10.0 m/s (D) a 20.0-kg mass moving at 1.00 m/s. What is the speed of a 1.0×10 3 -kg car that has a momentum of 2.0×10 4 kg•m/ s east?

## Momentum

E N D

### Presentation Transcript

1. Momentum

2. Which object has the greatest momentum? (A) a 5.00-kg mass moving at 10.0 m/s (B) a 10.0-kg mass moving at 1.00 m/s (C) a 15.0-kg mass moving at 10.0 m/s (D) a 20.0-kg mass moving at 1.00 m/s

3. What is the speed of a 1.0×103-kg car that has a momentum of 2.0×104 kg•m/ s east? (A) 5.0 × 10–2 m/s (B) 2.0 × 101 m/s (C) 1.0 × 104 m/s (D) 2.0 × 107 m/s

4. Impulse

5. Which two quantities can be expressed using the same units? (A) energy and force (B) impulse and force (C) momentum and energy (D) impulse and momentum

6. A 60-kg rollerskater exerts a 10-N force on a 30-kg rollerskater for 0.20 second. What is the magnitude of the impulse applied to the 30-kg rollerskater? (A) 50 N•s (B) 2.0 N•s (C) 6.0 N•s (D) 12 N•s

7. A 60-kg rollerskater exerts a 10-N force on a 30-kg rollerskater for 0.20 second. What is the magnitude of the change in momentum applied to the 30-kg rollerskater? (A) 50 kg•m/s (B) 2.0 kg•m/s (C) 6.0 kg•m/s (D) 12 kg•m/s

8. A 60-kg rollerskater exerts a 10-N force on a 30-kg rollerskater for 0.20 second. What is the magnitude of the change in momentum applied to the 60-kg rollerskater? (A) 50 kg•m/s (B) 2.0 kg•m/s (C) 6.0 kg•m/s (D) 12 kg•m/s

9. A 0.149-kilogram baseball, initially moving at 15 meters per second, is brought to rest in 0.040 second by a baseball glove on a catcher’s hand. What is the magnitude change in momentum exerted on the ball by the glove?

10. A 0.149-kilogram baseball, initially moving at 15 meters per second, is brought to rest in 0.040 second by a baseball glove on a catcher’s hand. The magnitude of the average force exerted on the ball by the glove is (A) 2.2 N (B) 2.9 N (C) 17 N (D) 56 N

11. Which situation will produce the greatest change of momentum for a 1.0-kilogram cart? (A) accelerating it from rest to 3.0 m/s (B) accelerating it from 2.0 m/s to 4.0 m/s (C) applying a net force of 5.0 N for 2.0 s (D) applying a net force of 10.0 N for 0.5 s

12. A 0.15-kilogram baseball moving at 20 m/s is stopped by a catcher in 0.010 second. The average force stopping the ball is (A) 3.0×10–2 N (B) 3.0×100 N (C) 3.0×101 N (D) 3.0×102 N

13. A 6.0-kilogram block, sliding to the east across a horizontal, frictionless surface with a momentum of 30 kg•m /s, strikes an obstacle. The obstacle exerts an impulse of 10 N•s to the west on the block. The speed of the block after the collision is (A) 1.7 m/s (B) 3.3 m/s (C) 5.0 m/s (D) 20. m/s

14. Elastic

15. Ball A of mass 5.0 kg moving at 20 m/s collides with ball B of unknown mass moving at 10 m/s in the same direction. After the collision, ball A moves at 10 m/s and ball B at 15 m/s, both still in the same direction. What is the mass of ball B? (A) 6.0 kg (B) 2.0 kg (C) 10. kg (D) 12 kg

16. A 1.2-kg block and a 1.8-kg block are initially at rest on a frictionless, horizontal surface. When a compressed spring between the blocks is released, the 1.8-kg block moves to the right at 2.0 m/s. What is the speed of the 1.2-kg block after the spring is released? (A) 1.4 m/s (C) 3.0 m/s (B) 2.0 m/s (D) 3.6 m/s

17. Inelastic

18. A 3.0-kg steel block is at rest on a friction-less horizontal surface. A 1.0-kg lump of clay is propelled horizontally at 6.0 m/s toward the block. Upon collision, the clay and steel block stick together and move to the right with a speed of (A) 1.5 m/s (B) 3.0 m/s (C) 6.0 m/s (D) 2.0 m/s

19. A woman (60-kg) with horizontal velocity (6 m/s) jumps off a dock into a stationary boat (120 kg). After landing in the boat, the woman and the boat move with velocity v2. Find v2

20. A 3.1-kilogram gun initially at rest is free to move. When a 0.015-kilogram bullet leaves the gun with a speed of 500 m/s, what is the speed of the gun? (A) 0.0 m/s (B) 2.4 m/s (C) 7.5 m/s (D) 500 m/s

21. At the circus, a 100-kg clown is fired at 15 m/s from a 500-kg cannon. What is the recoil speed of the cannon? (A) 75 m/s (B) 3.0 m/s (C) 15 m/s (D) 5.0 m/s

22. An 8.00-kilogram ball is fired horizontally from a 1.00 × 103-kg cannon initially at rest. After having been fired, the momentum of the ball is 2.40 × 103 kg•m/s east. Calculate the magnitude of the cannon’s velocity after the ball is fired.

23. An 8.00-kilogram ball is fired horizontally from a 1.00 × 103-kg cannon initially at rest. After having been fired, the momentum of the ball is 2.40 × 103 kg•m/s east. Calculate the magnitude of the cannon ball’s velocity after itis fired.

24. A 50-kilogram child running at 6.0 meters per second jumps onto a stationary 10-kilogram sled. The sled is on a level frictionless surface. Calculate the speed of the sled with the child after she jumps onto the sled.

25. A 1200-kilogram car moving at 12 meters per second collides with a 2300-kilogram car that is waiting at rest at a traffic light. After the collision, the cars lock together and slide. Eventually, the combined cars are brought to rest by a force of kinetic friction as the rubber tires slide across the dry, level, asphalt road surface. Calculate the speed of the locked-together cars immediately after the collision.

26. Extra

27. A 2.0-kg laboratory cart is sliding across a horizontal frictionless surface at a constant velocity of 4.0 m/s east. What will be the cart’s velocity after a 6.0-Newton westward force acts on it for 2.0 seconds? (A) 2.0 m/s east (B) 10 m/s east (C) 2.0 m/s west (D) 10 m/s west

28. A 1,200-kg car traveling at 10 m/s hits a tree and is brought to rest in 0.10 second. What is the magnitude of the average force acting on the car to bring it to rest? (A) 1.2×102 N (B) 1.2×103 N (C) 1.2×104 N (D) 1.2×105 N

29. A 50-kg student threw a 0.40-kg ball with a speed of 20 m/s. What was the magnitude of the impulse that the student exerted on the ball? (A) 8.0 N•s (B) 78 N•s (C) 4.0 × 102 N•s (D) 1.0 × 103 N•s

30. The instant before a batter hits a 0.14-kilogram baseball, the velocity of the ball is 45 meters per second west. The instant after the batter hits the ball, the ball’s velocity is 35 meters per second east. The bat and ball are in contact for 1.0 × 10–2 second. Calculate the initial momentum of the ball.

31. The instant before a batter hits a 0.14-kilogram baseball, the velocity of the ball is 45 meters per second west. The instant after the batter hits the ball, the ball’s velocity is 35 meters per second east. The bat and ball are in contact for 1.0 × 10–2 second. Calculate the final momentum of the ball.

32. The instant before a batter hits a 0.14-kilogram baseball, the velocity of the ball is 45 meters per second west. The instant after the batter hits the ball, the ball’s velocity is 35 meters per second east. The bat and ball are in contact for 1.0 × 10–2 second. Calculate the change in momentum of the ball.

33. The instant before a batter hits a 0.14-kilogram baseball, the velocity of the ball is 45 meters per second west. The instant after the batter hits the ball, the ball’s velocity is 35 meters per second east. The bat and ball are in contact for 1.0 × 10–2 second. Calculate the impulse that acted on the ball.

34. The instant before a batter hits a 0.14-kg baseball, the velocity of the ball is 45 meters per second west. The instant after the batter hits the ball, the ball’s velocity is 35 meters per second east. The bat and ball are in contact for 1.0 × 10–2 second. Calculate the magnitude of the average force the bat exerts on the ball while they are in contact.

35. Calculate the magnitude of the impulse applied to a 0.75-kilogram cart to change its velocity from 0.50 meter per second east to 2.00 meters per second east.

36. A 1000-kilogram car traveling due east at 15 meters per second is hit from behind and receives a forward impulse of 6000 Newton-seconds. Determine the magnitude of the car’s change in momentum due to this impulse.

37. A 60-kilogram student jumps down from a laboratory counter. At the instant he lands on the floor his speed is 3 meters per second. If the student stops in 0.2 second, what is the average force of the floor on the student? (A) 1×10–2 N (B) 9×102 N (C) 1×102N (D) 4N

38. A motorcycle being driven on a dirt path hits a rock. Its 60-kilogram cyclist is projected over the handlebars at 20 meters per second into a haystack. If the cyclist is brought to rest in 0.50 second, the magnitude of the average force exerted on the cyclist by the haystack is (A) 6.0 × 101 N (B) 5.9 × 102 N (C) 1.2 × 103 N (D) 2.4 × 103 N

39. A 2.0-kg body is initially traveling at a velocity of 40 m/s east. If a constant force of 10 Newtons due east is applied to the body for 5.0 seconds, the final speed of the body is (A) 15 m/s (B) 65 m/s (C) 25 m/s (D) 130 m/s

More Related