PHYS 101 Quiz Energy and Conservation

PHYS 101 Quiz: Energy and Conservation Laws

1. What are the SI units of momentum?
2. Consider a situation where you exert a force F on a crate of mass m, moving it at a speed v a distance d across a floor in a time interval t.
3. A kid slides down an icy (frictionless) hill starting from rest. At the top his gravitational potential energy is 500 J.
4. The mass of 1 cubic meter of fresh water at the top of a 100 m hydroelectric dam is 1,000 kg and it has a potential energy of 980,000 N. At the bottom of the dam, the speed of the moving water is
5. If a force on an object is aimed opposite the direction of the object’s velocity, the force does
6. The mass of 1 cubic meter of fresh water is 1,000 kg. At the top of a 100 m hydroelectric dam the potential energy of the cubic meter of water is
7. The energy of a ball rolling up an inclined plane
8. Consider a situation where a constant force of 25 N acts on an object having a mass of 2 kg for 3 seconds.
9. Consider a situation where a skater pulls her arms inward, causing her rotation rate to speed up.
10. You carry a 20-N box 5 m horizontally across a room. The work you do is
11. About how many 100-W light bulbs would you have to light up to use energy at the rate of one horsepower?
12. When a freely falling object reaches its terminal speed,
13. Using a lever to move a rock reduces the force a person must exert. What does it do to the work the person must do?
14. Work is done on an object when
15. Consider a situation where two moving objects collide and rebound from each other.
16. The measure of a body’s resistance to being rotated is its angular momentum.
17. Consider a situation where you exert a force F on a crate of mass m, moving it at a speed v a distance d across a floor in a time interval t.
18. Consider a situation where a skater pulls her arms inward, causing her rotation rate to speed up.
19. Consider a situation where a skater pulls her arms inward, causing her rotation rate to speed up.
20. A person runs up a long flight of stairs in 10 seconds. If the person’s weight is 600 N and the vertical height of the stairs is 20 meters, the person’s power output is 1,200 W.
21. The energy of a ball rolling up an inclined plane is an example of both kinetic and gravitational potential energy.
22. For a body oscillating at the end of a spring, the energy is only elastic potential energy.
23. The momentum of an object never changes.
24. The energy stored in a stretched spring is an example of gravitational potential energy.
25. A rocket can never go faster than the speed of its exhaust.
26. Select the closest matching pairs possible. 3 pts for each response.
27. What is the baseball’s final speed when it impacts the ground using