Chapter 7: Work, Power, and Energy
Chapter Objectives
After this chapter, you will be able to:
- Explain how an object must be displaced for a force on it to do work.
- Explain how relative directions of force and displacement determine whether the work done is positive, negative, or zero.
- Explain work as a transfer of energy and net work as the work done by the net force.
- Explain gravitational potential energy in terms of work done against gravity.
- Show that the gravitational potential energy of an object of mass m at height h on Earth is given by PEg = mgh.
- Explain the law of the conservation of energy.
- Calculate power by calculating changes in energy over time.
- Explain the human body’s consumption of energy when at rest vs. when engaged in activities that do useful work.
- Calculate the conversion of chemical energy in food into useful work.
