## Number of photons

$c=\lambda v$

405161024
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Joined: Fri Sep 28, 2018 12:25 am

### Number of photons

If you are given the energy of a labor and its wavelength how do you calculate the number of photons?

timschaeffer Dis 1J
Posts: 38
Joined: Fri Sep 28, 2018 12:18 am

### Re: Number of photons

I assume you mean laser and not labor. The energy per each photon is given by E= hc/wavelength, where h is planck's constant, c is the speed of light, and the wavelength is the wavelength of the laser. You then divide the energy of the laser by the energy per photon to get the number of photons being emitted.