Question

Momentum of a photon of wavelength $\lambda$ is:

• A. $h/\lambda$
• B. Zero
• C. $h\lambda /c^2$
• D. $h\lambda /c$

Answer 1

The correct option is A $h/\lambda$

Momentum of a photon of wavelength $\lambda$ is:
The energy of light $E=\frac{hc}{\lambda }$....(1)
The energy of light $E=m{c}^2$ ....(2)
(1) $=$ (2)
$\frac{hc}{\lambda }=m{c}^2$
$\frac{h}{\lambda }=mc=$ Momentum.