In calculating the energy of a photon of light, we need the relationship for energy and the frequency which is expressed as:
E=hv
where h is the Planck's constant (6.626 x 10-34 J s)and v is the frequency.
E = 6.626 x 10-34 J s (7.33 x 10^14 /s) = 4.857 x 10^-19 J
