Monochromatic light of wave length $632.8\;nm$ is produced by a helium - neon laser. The power emitted is $9.42\;mw$. Find the energy and momentum of each photon in the light beam

Question

$\begin{array}{1 1} E= 3.14 \times 10^{-19}\;J \; P= 1.05 \times 10^{-27}\;kgms^{-1} \\ E = 3.14 \times 10^{-19}\;kJ \; P= 1.05 \times 10^{-27}\;kgms^{-1} \\ E= 1.05 \times 10^{-27}\;J \; P= 3.14 \times 10^{-19}\;kgms^{-1} \\ E= 1.05 \times 10^{-9}\;J \; P= 3.14 \times 10^{-27}\;kgms^{-1} \end{array} $