A radiation of energy E falls normally on a perfectly reflecting surface. What is the momentum transferred to the surface ?
Answer & explanation
Correct answer: option 2
Initial Momentum of photon $P_i = \frac{E}{c}$
Final Momentum of photon after reflection $P_f = \frac{E}{c}$
Change in momentum is $\Delta P = \frac{2P}{c}$
$\Rightarrow \text{Momentum Transfered }= \frac{2P}{c}$