Chapter 2

12. Kinetic energy is energy in action. It is seen in the constant movement of the tiniest particles (atoms) and in larger atoms (a bouncing ball). Kinetic energy does work by moving objects, which then can move or push other objects. Potential energy is stored energy that has the capability to do work, but is not doing so. When potential energy is released, it becomes kinetic energy and is capable of doing work. Chemical energy is the form of energy stored in the bonds of chemical substances. When chemical reactions occur that rearrange the atoms of the chemicals in a certain way, the potential energy is unleashed and becomes kinetic energy. Chemical energy in the form of ATP is the most useful form of energy in living systems because it is used to run all functional processes. Electrical energy results from the movement of charged particles. At home, electrical energy is found in the flow of electrons in the wiring. In your body, electrical currents are generated when ions move along or across cell membranes. The nervous system uses nerve impulses (electrical currents) to transmit messages from one part of your body to another. Electrical currents traveling across the heart stimulate it to contract (beat) and pump blood. Mechanical energy is energy directly involved in moving matter. An example would be how your legs provide the mechanical energy that move the pedals when riding a bicycle. Radiant energy or electromagnetic energy is energy that travels in waves. These waves which vary in length are collectively called the electromagnetic spectrum and include visible light, infrared waves, radio waves, ultraviolet waves, and X-rays.