Question

A photon has a wavelength of 500nm what is the energy associated

Answer 1

Given: Plank's constant h = 6.626 x 10⁻³⁴ J.s   

           Speed of light c = 2.998 x 10⁸ m/s

            Wavelength  λ = 500 nm  convert to meter = 5 x 10⁻⁷ m

Required: Energy E =?

Formula: E = hc/λ

               E = (6.626 X 10⁻³⁴ J.s)(2.998 X 10⁸ m/s)/5 x 10⁻⁷ m

               E = 3.97 X 10⁻¹⁹ J  or in termS of electron volt

               E = 2.48 eV