Why do the frequencies of EM waves increase and the wavelength decrease?

Answer 1

Frequency refers to the vibration of some object that is creating a wave; in the case of electromagnetic waves, it would normally be an electron. Let us then imagine a vibrating electron. Every time it vibrates, it produces a wave. If it vibrates a million times a second it produces a million waves. The electromagnetic radiation always travels at the same speed, the speed of light, sometimes known as c, which is equal to 300,000 kilometers per second. So if there are a million waves per second, they will fit into the space of 300,000 kilometers, which makes each wave a third of a kilometer in length. Increase the frequency and you increase the number of waves, but the total distance remains the same, so you have to fit more waves into the same distance, hence, each individual wave is smaller, meaning it has a shorter wavelength. So if the electron is now vibrating at a billion times a second, it produces a billion waves, and they still have to fit into 300,000 kilometers, hence, each wave is now a third of a meter in length, rather than a third of a kilometer. If the electron vibrates at a trillion times a second, the waves are then a third of a millimeter in length. And so forth.