Momentum and Its Conservation

1. Momentum and Its Conservation Review

2. Momentum is a ___ quantity. 10 • scalar • vector

3. 10 Momentum can be calculated by multiplying mass by • Acceleration • Velocity • Impulse • Time

4. 10 If no net force acts on a body • The velocity of the body in constant • The body is accelerating • The momentum of the body is zero • The momentum of the body is increasing

5. 10 The greatest change in momentum will be produced by • A large force acting over a long time • A small force acting over a short time • A large force acting over a short time • A small force acting over a long time

6. 10 If an object with a velocity of 50 m/s has the same momentum as that of a 10 kg mass having a velocity of 20 m/s, the mass of the object is • Greater than 10 kg • Less than 10 kg • 10 kg

7. 10 Impulse can be represented by • Δv/ Δt • F Δt • Mv • None of these

8. 10 When a golfer hits a golf ball, the force exerted by the ball on the club is ___ that exerted by the club on the ball. • Equal to • Greater than • Less than

9. 10 When a golf club hits a golf ball, the change in momentum of the ball is ___ the change in momentum of the club. • Equal to • Greater than • Less than

10. 10 When a golf club hits a golf ball, the change in velocity of the ball is ___ that of the club. • Equal to • Greater than • Less than

11. 10 If an object moving at a rate of 20 m/s collides with a stationary object and the two objects move away together, the velocity of the combined objects will be • Greater than 20 m/s • Less than 20 m/s • 20 m/s

12. 10 The collision described in the previous question would be classified as an ____ collision. • Elastic • Inelastic

13. 10 Two moving objects collide and move apart on paths that are 120o apart. The total momentum of the objects after the collision is ___ the total momentum before the collision. • Equal to • Greater than • Less than

14. 10 If the momentum of an object changes and its mass remains constant, • Its velocity is changing • It is accelerating • There is a force acting on it • All of the above • None of the above

15. 10 The reason that crumple zones are used in cars is that they • Increase the force of impact in a collision • Decrease the momentum of a collision • Decrease the impulse in a collision • Increase the time of impact in a collision

16. 10 Which has the greater momentum: a 145 g baseball traveling at 40.0 m/s or a 45 g golf ball traveling at 67.0 m/s? • The baseball • The golf ball • Both have the same momentum

17. 10 What impulse is needed to stop a 45 g mass traveling at 42 m/s? • 1.9 N.s • 3.0 N.s • 190 N.s • 1900 N.s

18. 10 A force of 500 N is used to stop an object with a mass of 50 kg moving at 2 m/s. How long will it take to bring the object to a full stop? • 0.50 seconds • 0.10 seconds • 0.15 seconds • 0.20 seconds

19. 10 Which type of collisions obey the law of conservation of momentum? • Elastic • Inelastic • Both elastic and inelastic • Neither elastic nor inelastic

20. 10 Which of the following is NOT a vector quantity? • Acceleration • Force • Momentum • Time

21. An egg is thrown against a wall. A second egg of equal mass is thrown with the same velocity at a sheet. Which egg experiences the greater impulse? 10 • The egg thrown at the wall. • The egg thrown at the sheet. • Both experience the same impulse.

22. 10 A system is said to be closed if • No external force acts on it • The momentum of each object in the system remains the same • Objects cannot enter or leave the system • Objects can enter but not leave the system

23. 0 An internal force ___ the total momentum of a system. • Increases • Decreases • Does not change