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nutzweb
Oct2-05, 11:41 PM
just wanna ask what are electromagnetic waves and how are they produced?
also, do you where i can get a simple application of EM waves? just really need it... thanks!

JoAuSc
Oct3-05, 01:48 AM
When an electric field changes, it creates a magnetic field, and when the magnetic field changes, it creates an electric field. When you have a positive charge and a negative charge close together and you oscillate them, the electric field will create a magnetic field which will create an electric field which will create a magnetic field, and so on. This is an electromagnetic wave, an oscillation in the electric and magnetic fields. By rearranging Maxwell's equations it can be shown that electromagnetic waves travel at 3.0 * 10^8 m/s. There are a bunch of details I'm missing here, such as how electromagnetic waves fit in with quantum mechanics.

nutzweb
Oct5-05, 07:30 AM
do radio and radar considered as applications of electromagnetic waves? if then, how do electromagnetic waves function in those applications?