If radio waves are invisible to the human eye, how can one measure wavelength?

Question

If radio waves are invisible to the human eye, how can one measure wavelength?

In: Physics

Answer 1

Radio waves move the speed of light, and their wavelength is the inverse of their frequency. So you can measure the frequency and use the simple relationship (speed of light) = wavelength x frquency.

In practice, an easy way to learn the wavelength or frequency of a radio wave is to use an antenna (which is why radios have them). The radio waves push the electrons in the antenna back and forth as they hit it. So you can hook that antenna up to an amplifying circuit and look at the electronic wave instead of the radio wave itself. This is easily done with an oscilloscope.