Question

Photon of frequency $v$ has a momentum associated with it. If $c$ is the velocity of light, the momentum is

• A. $\frac{hv}{c}$
• B. $\frac{v}{c}$
• C. $hvc$
• D. $\frac{hv}{c^2}$

Answer 1

Answer: (A)

Energy of a photon, $E=hv\dots (i)$
Also, $E=pc\dots (ii)$
Where $p$ is the momentum of a photon.
From (i) and (ii), we get
$hv=pc$ or $p=\frac{hv}{c}$