The equation E = mc^2 is a special case of the more general equation for energy, where m represents the rest mass of an object. However, photons are massless particles, which means they do not possess rest mass. The equation E = mc^2 is not applicable to photons.
For photons, the energy (E) is given by E = hf, where h is the Planck's constant and f is the frequency of the photon. Additionally, the speed of light (c) can be related to the wavelength (λ) and frequency (f) of a photon using the equation c = λf.
Combining these equations, we can express the energy of a photon in terms of its wavelength as:
E = hf = (hc)/λ
From this equation, we can determine the energy of a photon for a given wavelength. However, since photons have no rest mass, there is no mass term (m) involved in these calculations.