Question

Nitrogen laser produces a radiation at a wavelength of 337.1 nm. If the number of photons emitted is $5.6\times {10}^{24}$, calculate the power of this laser.

Answer 1

The power of the laser is,
$E=\frac{Nhc}{\lambda }$

where

E=power of the laser

N=No of photons =$5.6\times {10}^{24}$

h=Planks constant=$6.626\times {10}^{-34}$

c= speed of light=$3.0\times {10}^8$

$E=\frac{5.6\times {10}^{24}\times 6.62\times {10}^{-34}\times 3\times {10}^8}{337.1\times {10}^{-9}}=3.3\times {10}^{6}J/s=3.3\times {10}^{6}W$