Electromagnetic waves
waves are all around US, rippling on water, rolling across a field of corn or keeping a centipede's legs organized-as well as bringing us sound and light. Waves allow something to go from one place to another without anything moving very much, making them of vital importance to communication. Waves usually occur in a medium that can store and pass on energy in two different but related forms. Sound, for instance, can travel in anything able to store energy as motion and pressure. For electromagnetic waves the the medium is space itself, which can store energy in electric and magnetic form. Scottish mathematician James Clerk Maxwell (1831-1879) extended the work done by Michael Faraday (p. 10). He realized that the close relationship between electricity and magnetism made this kind of wave possible. His calculations showed that the wave would travel at the speed of light, making him suspect that light itself was an electromagnetic wave. In 1888 Heinrich Hertz generated waves electrically and showed that they behave just like light, confirming Faraday's and Maxwell's ideas.