Fermilab

On the previous page, we saw how to create EM waves. On this page, I show how we describe them.

The electric and magnetic components of the wave are perpendicular to each other, and also perpendicular to the direction in which the wave is traveling. There are three very important parameters describing an EM wave: its frequency, , the amplitudes and , and the speed v of the wave. ( I said three parameters, because the amplitudes are not independent, but this is is not important for our discussion.)

The amplitudes of the waves control how bright the wave (or its source) is. Amplitude controls the intensity of the radiation. The higher the amplitude, the brighter the source is.

I know, I still haven't said a single word about how light relates to the things described above, but we are very close.

Please go to the next page to find out the role of the frequency,