In physics, frequency refers to the number of waves that pass a fixed point in a given amount of time. It is usually measured in hertz (Hz), where one hertz equals one wave cycle per second.

Higher frequency means more wave cycles in a given period, which in sound waves translates to a higher pitch.

As you adjust the frequency, notice how the number of wave cycles increases or decreases. This visualizes how frequency affects the wave's pitch in the case of sound waves or the energy in other types of waves.