Amplitude:

In adding up to the period or frequency, the wavelength, and the propagation speed, waves have the other property: amplitude. This is the height or strength of the wave, the associative distance among peaks and troughs. Whenever all other factors are steady, the more energy a wave has, the greater is its amplitude.

The energy of the light wave is directly proportional to the amplitude, directly proportional to frequency, and inversely proportional to the wavelength. The similar is true for x-rays, gamma rays, UV, IR, and radio waves. Though, for waves on the surface of a liquid, such exact mathematical associations do not apply. The Amplitude is at times, though not always, an accurate indicator of the energy in a wave.