- #1
jackychenp
- 28
- 0
From EM, the energy of electromagnetic wave in unit volume is [itex] \varepsilon_0 E^2[/itex]. Does that mean the number of photon is [itex]\varepsilon_0 E^2/\hbar\omega [/itex]( [itex]\omega [/itex] is frequency of wave)? In 1-D, [itex]E=E_0cos(\omega t+kx)[/itex], then the number of photon in average is [itex]\frac{1}{(2\pi/\omega)}\int_{0}^{2\pi /\omega}\varepsilon_0 E_0^2cos^2(\omega t+kx)/\hbar\omega dt = \varepsilon_0 E_0^2/\hbar\omega[/itex]. This result looks very weird. Please correct me if something is wrong!