Consider the light from a green laser pointer (wavelength = 532 nm).

Question

What is the energy of 1 photon form this laser?

If the laser emits 1.30×10^-2 J during a pulse, how many moles
of photons are emitted during the pulse?

Answer 1

#1. E = hf = 6.62607015*10^-34 * 3.0*10^8/532*10^-9 = 3.7365*10^-19 J/photon

#2. 1.30*10^-2 J * 1photon/3.7365*10^-19 J/photon * 1mole/6.023*10^23photons = 5.776 *10^-8 moles