- Anthony is standing on the top of a building 10 m high holding a 7 kg bowling ball. Mildred dug a 2 m deep hole next to the base of the building. What is the gravitational potential energy of the bowling ball relative to the bottom of the hole?
- 137.2 J
- 548.8 J
- 686.0 J
- 823.2 J
- A hockey player pushing a practice net across an ice rink becomes more and more tired while doing so. The force exerted over the 30 m traveled followed the graph above. How much work did the hockey player do in pushing the practice net?
- 10 J
- 600 J
- 1200 J
- 18,000 J
- In an inelastic collision, what quantities are conserved?
- Momentum only
- Kinetic energy only
- Momentum and kinetic energy
- Neither momentum nor kinetic energy
- A 15 kg ball is thrown straight upwards with a speed of 20 m/s. What is the maximum height the ball reaches?
- 14.0 m
- 19.8 m
- 20.4 m
- 40.8 m
- A man pushes a crate across a coarse floor with an efficiency of 50%. Which of the following is true?
- Energy is not conserved, because the efficiency is less than 100%.
- Part of the man's work done goes into moving the crate, while the other part of his work is done against friction.
- The work done by the crate equals the work done on the crate.
- The work done in moving the crate equals the work done by the man.
| | - A 70 kg woman who wants to climb up the 900 m face of the El Capitan vertical rock formation in Yosemite ponders her fate were she to fall without using a safety rope. How fast would she be traveling at the bottom when she hits the ground were she to fall from the top of the cliff's face?
- 13.6 m/s
- 93.9 m/s
- 132.8 m/s
- 17,640 m/s
- Which bar graph above might represent the kinetic energy (KE), gravitational potential energy (GPE), and elastic potential energy (EPE) of a pole vaulter just before she leaves the ground at the beginning of the vault?
- 1
- 2
- 3
- 4
- For a typical car, approximately 65% of the energy in the fuel is radiated away as heat, 13% is output as work in moving the car, 10% is spent overcoming friction, 7% is spent idling rather than moving, and 5% runs various accessories (such as the air conditioning and radio). What is the efficiency of the typical car?
- 13%
- 20%
- 23%
- 30%
- Two different hot metal objects, both at the same temperature, are each added to the same quantity of water that is at room temperature. Which metal will raise the water to a higher temperature?
- The metal with the higher specific heat
- The metal with the higher mass
- Neither, because both metals are at the same temperature
- It will depend on both the mass and the specific heat of each metal
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