What is the relationship between wavelength and energy of a photon?

The relationship between wavelength and energy of a photon is described by the equation ( E = \frac{hc}{\lambda} ), where ( E ) is the energy of the photon, ( h ) is Planck's constant, ( c ) is the speed of light, and ( \lambda ) is the wavelength. According to this equation, energy and wavelength are inversely related. As the wavelength (( \lambda )) decreases (indicating shorter wavelengths), the energy (( E )) of the photon increases. This principle underlines why shorter wavelengths correspond to higher energy; photons associated with ultraviolet or blue light, for example, have shorter wavelengths and carry more energy compared to those associated with red light or infrared light, which have longer wavelengths.

This fundamental concept explains why ultraviolet radiation can cause damage to skin (due to its high energy) while infrared radiation does not have the same effect since it is lower in energy. The nature of light as a wave-phenomenon and the quantization of energy in photons combine to form this essential understanding of the electromagnetic spectrum, providing insights not only into physics but also into practical applications like spectroscopy and photochemistry.