The energy of a photon is given by
where h is the Planck constant and f is the frequency of the light.
Given the relationship between the frequency f, the wavelength
and the speed of light c for an electromagnetic wave:
we can rewrite the energy of the photon as
and by substituting
, 
and 
, we get the wavelength of the photon:
where h is the Planck constant and f is the frequency of the light.
Given the relationship between the frequency f, the wavelength
we can rewrite the energy of the photon as
and by substituting
