For some purposes a photon—a quantum of electromagnetic radiation can be treated as a classical electromagnetic wave train with energy au = ħw, where ħ is planck's reduced constant and w is the angular frequency of the wave. photons are circularly polarized. a. in einstein's mechanics the mass m of a particle of energy eand momentum p is given by the relation e? - p²c2 = m4, where c is the speed of light in vacuum. calculate the mass of the photon, defined in this way. b. the spin quantum number s of a particle is its spin angular momentum s divided by planck's reduced constant ħ. calculate the spin quantum number of the photon, thus defined