Question

A photon of energy $hv$ and momentum $hv/c$ collides with an electron at rest. After the collision, the scattered electron and the scattered photon each make an angle of $45^{\circ }$ with the initial direction of motion. The ratio of frequency of scattered and incident photon is

• A. $\sqrt{2}$
• B. $\sqrt{2}-1$
• C. $2$
• D. $1/\sqrt{2}$

Answer 1

Answer: (A)

$\frac{\text{Frequency of photon}}{\text{Frequency of scattered photon}}$

$=\frac{v}{v\cos 45^{\circ }}$
$=\frac{1}{1/\sqrt{2}}$
$=\sqrt{2}$