Energy of photon = hc/λ where h is the Planck constant (h = 6.6260693*10-34 joule.sec), c is speed of light (c = 299792458 m/sec) and λ is wavelength (λ = 670.8*10-9 m)
So: Energy = 6.6260693*10^(-34)*299792458/(670.8*10^-9) ≈ 3*10-19 joules
Energy of photon = hc/λ where h is the Planck constant (h = 6.6260693*10-34 joule.sec), c is speed of light (c = 299792458 m/sec) and λ is wavelength (λ = 670.8*10-9 m)
So: Energy = 6.6260693*10^(-34)*299792458/(670.8*10^-9) ≈ 3*10-19 joules
