Unit 3 Test: Energy and Momentum

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Unit 3 Test: Energy and Momentum

Choose the best answer. Do not write on the test booklet

Good luck!

1. The energy of motion is called:

A. Gravitational Energy

C. Elastic Energy

B. Kinetic Energy

D. None of the above

2. An example of chemical energy is:

A. The energy stored in food

C. The energy in a falling weight

B. The energy in a rolling rock

D. None of the above

3. If 800 J of work are done by a 100 N force, over what distance does the force act?

A. 200 m

C. 0.125 m

B. 80,000 m

D. None of the above

4. What force is required to do 3500 J of work over a distance of 70 m?

A. 50 N B. 500 N

C. 245,000 N D. None of the Above

5. If 30 N of force pushes a block 20 m, how much work is done?

A. 1.5 J

C. 600 J

B. 0.66 J

D. None of the above

6. The tendency of an object to resist changes to its motion best defines:

A. Energy

C. Work

B. Momentum

D. None of the above

7. How much energy does a 1000 kg car have if it is traveling at 20 m/s?

A. 2 x 10 5 J B. 1.96 x 10 5 J

C. 1 x 10

4

J D. None of the Above

8. If a 3000 kg wooden rabbit is pushed so that it goes from rest to a velocity of 4 m/s, how much work was done on the rabbit?

A. 117600 J

C. 24000 J

B. 12000 J

D. None of the Above

9. If 10 J of work is done on an object, what will be the change in the energy it possesses?

A. 10 J

C. 0 J

B. 98 J

D. None of the above

10. If a 2 kg cantaloupe has 9 J of work done on it. How much does its velocity increase?

A. 18 m/s B. 4.5 m/s

C. 3 m/s D. None of the above

11. A 4 kg bowling ball rolls down a hill which is 15 m high. If it has a velocity of 10 m/s at the bottom of the hill how much work was done on the ball by friction or other forces?

A. 40 J

C. 150 J

B. 60 J

D. None of the Above

12-16. A 0.5 kg pendulum is released from a height of 0.4 m.

12. What is the maximum potential energy of the pendulum?

A. 0.2 J B. 1.96 J

C. 0.04J D. None of the Above

13. What is the Kinetic Energy of the pendulum at the bottom of its path?

A. 0.2 J

C. 0.04J

B. 1.96 J

D. None of the Above

14. What is the velocity of the pendulum at the bottom of its path?

A. 1.96 m/s B. 0.4 m/s

C. 7.84 m/s D. None of the Above

15. How much potential energy does the pendulum have when it is at a height of 0.2 m?

A. 0.10 J

C. 3.92 J

B. 0.98 J

D. None of the Above

16. What is the velocity of the pendulum when it is 0.2 m above the lowest point on its path?

A. 1.98 m/s

C. 2.80 m/s

B. 1.40 m/s

D. None of the Above

17-20. While on a training flight Ms. Hasselbring drops her Pez Dispenser (m = 0.001 kg) out of an airplane. If the airplane was flying at an altitude of 1 million m (1 x 10

6

m):

17. What is the gravitational potential energy of the Pez dispenser?

A. 5 x 10

8

J B. 0.0049 J

C. 9800 J D. None of the above?

18. Right before the Pez Dispenser hits the ground, how much Gravitational Potential

Energy does it have?

A. 5 x 10

8

J

C. 9800 J

B. 0.0049 J

D. None of the above?

19. If we are in physics land (no terminal velocity) what is the velocity of the Pez dispenser right before it hits the ground?

A. 4427 m/s

C. 54 m/s

B. 2.214 m/s

D. None of the Above

20. What is the velocity of the pez dispenser when it is 9 x 10

5

m above the ground?

A. 1.96 x 10

6

m/s B 1.4 x 10

3

m/s

C. 54 m/s D. None of the Above

21. An armadillo and an elephant are racing each other. If they start out at the same speed, then which has more kinetic energy?

A. The Elephant

C. Mr. Baden

B. The Armadillo

D. They have the same KE

22-25. Give the following a rank in order of kinetic energy from lowest to highest if they are all traveling at the same speed. Unicycle, Mack Truck, Motorcycle, and 4 door sedan

(1 means the lowest KE, 4 is the highest KE), you should use each number once over the next 4 questions.

22. Unicycle

A. 1

C. 3

B. 2

D. 4

23. Mack Truck, with loaded trailer.

A. 1

C. 3

B. 2

D. 4

24. Motorcycle

A. 1

C. 3

B. 2

D. 4

25. Standard 4 door car.

A. 1

C. 3

B. 2

D. 4

26. A family of 4 is standing at the edge of the Grand Canyon. Pick the correct order of their potential energies from smallest to largest (Assume that each member is average sized for their age and gender).

A. Father, Mother, 10 year old son, 1 year old daughter

B. 10 year old son, Father, 1 year old daughter, Mother

C. 1 year old daughter, 10 year old son, Mother, Father

D. None of the above.

27. In the energy conservation/ energy conversion lab (with the pipe insulation and the marble) what caused the marble to not go back to its starting height?

A. Didn’t start with enough energy

B. Lost energy due to friction

C. Gained energy while it rolled.

D. None of the above

28. Which is the best example of elastic potential energy?

A. A coiled spring B. Gasoline

C. A book on the edge of a table D. All of the above.

29-30. For the next two questions refer to the following graph of a pendulum’s energy vs. time.

29. At which point on the graph is the pendulum at its highest point?

A. A

C. C

B. B

D. D

30. At which point does the pendulum have its greatest velocity?

A. A B. B

C. C D. D

31. A 6 kg hawk swoops down at its prey with a velocity of 20 m/s, when it is 8 m above the ground how much total energy does it have?

A. 1670.4 J

C. 1176.0 J

B. 1200.0 J

D. None of the above

32. How much momentum doe s 30 kg dog have if it is running at 5 m/s?

A. 6 Ns

C. 150 Ns

B. 0.166 Ns

D. None of the above

33. How much momentum does a 100 kg refrigerator have if it is falling at a velocity of

10 m/s?

A. 100 Ns

C. 10,000 Ns

B. 10 Ns

D. None of the above

34. A 60 kg skateboarder is on her board, not moving relative to the ground, when she throws a 10 kg medicine ball with a velocity of -5 m/s what is the velocity of the skateboarder?

A. 6.0 m/s

C. 10.0 m/s

B. 0.83 m/s

D. None of the Above

35. If the space shuttle (mass = 9,900 kg, carrying a 100 kg gas canister; total mass =

10,000 kg ) is floating forward at 3 m/s what velocity would 100 kg of gas have to be shot forward with to stop the shuttle’s motion?

A. 300 m/s B. 30,000 m/s

C. 29,700 m/s D. None of the above

36. A bus takes longer to stop than a car because it has ______________ momentum than a car.

A. Less

C. The same

B. More

D. momentum

37. The longer stopping time for buses means that seatbelts aren’t as important because:

A. High seats prevent whiplash

B. Longer stopping time spreads out the force of impact, keeping riders in their seats

C. Buses don’t get hit as hard in accidents

D. None of the above

38. A 5 kg bowling ball (A) is rolled (with a velocity of 7.5 m/s) into an identical bowling ball (B) which is not moving. What is the resulting velocity of bowling ball B?

A. 0 m/s B. 37.5 m/s

C. 7.5 m/s D. None of the Above

Use the following information to answer questions 39-40

In space Asteroid Ketchup has a mass of 200 kg and is traveling at 15 m/s when it hits

Asteroid Mustard which has a mass of 300 kg and is traveling in the same direction at 6 m/s.

39. What is the momentum of the system, of Ketchup and Mustard, before they hit each other?

A. 3000 Ns

C. 4800 Ns

B. 1800 Ns

D. None of the above

40. After the collision Asteroid Mustard has a velocity of 8 m/s, what is the velocity of

Asteroid Ketchup at that time?

A. 24 m/s

C. 8 m/s

B. 3 m/s

D. None of the Above

41. Impulse is _____________ multiplied by ____________.

A. Momentum, Force

B. Force, Time

C. Mass, Velocity

D. None of the Above

42. If a llama feels an impulse of 55 Ns applied to it, what will its momentum change by?

A. 5 Llamas

C. 0 Ns

B. 55 Ns

D. None of the Above

43. 8 dogs pull a 100 kg sled with a force of 160 N for 45 s. What is the change in velocity of the sled?

A. 800 m/s

C. 72 m/s

B. 12.5 m/s

D. None of the Above

44. If you want to accelerate an 800 kg car from rest to 10 m/s in 20 s, how much force do you need to apply to it?

A. 400 N

C. 8000 N

B. 800 N

D. None of the Above

45. A falling object’s potential energy becomes kinetic energy as it loses altitude and gains speed. This is an example of:

A. Energy Transfer

C. Energy Transformation

B. Energy Flow

D. None of the Above

46. When a sliding objects slows down because it is losing energy due to friction, what form is the lost energy taking?

A. Motion

C. Light

47. Terminal Velocity is:

B. Heat

D. None of the above

A. A fatal illness

B. A way to transfer energy

C. The highest speed an object will fall at

D. None of the above

48. According to the First Law of Thermodynamics if object A is in equilibrium with object B; and Object B is in equilibrium with Object C then:

A. Entropy Increases

B. Absolute Zero is the lowest possible temperature

C. A is in Equilibrium with C

D. None of the above

49. Entropy is:

A. A measure of disorder

C. A measure of heat

50. A Rube Goldberg machine includes:

A. Energy Transfers

C. Multiple Steps

B. A measure of temperature

D. None of the Above

B. Energy Transformations

D. All of the Above

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