Final answer:
The distance between two crests of a wave is known as the wavelength of the radiation. It is inversely proportional to the energy of the radiation.
Step-by-step explanation:
The distance between two crests of a wave is known as the wavelength of the radiation. It is the distance between any two consecutive identical points on the waveform. Wavelength is inversely proportional to the energy of the radiation, meaning that shorter wavelengths have higher frequency and vice versa.