CHEM 130 Study Guide - Midterm Guide: Tennis Ball, Negative Number
Document Summary
If the speed of a moving body increases, then its kinetic energy increases. If the speed of a moving body decreases, then its kinetic energy decreases. When a tennis ball is served its kinetic energy increases, when an airplane lands its kinetic energy decreases, and when a bullet is shot from a pistol its kinetic energy increases. If work is done to change the position of an object in a field, then its potential energy increases as a result of the change. If the change is in the opposite direction, the potential energy of the object decreases and the potential energy lost by the object could be used to do work. An everyday example is the potential energy of your body in the earth"s gravitational field. When you climb a flight of stairs you do work, and your potential energy increases. When oppositely charged objects come together due to attractive forces, the potential energy decreases.
