Q. Radiations of intensity 0.5 Wm$^{-2}$ are striking a metal plate. The pressure on the plate is
A) $0.166 \times 10^{- 8}\ {Nm}^{- 2}$
B) $0.332 \times 10^{- 8}\ {Nm}^{- 2}$
C) $0.111 \times 10^{- 8}\ {Nm}^{- 2}$
D) $0.083 \times 10^{- 8}\ {Nm}^{- 2}$
Explanation
(a) Intensity or power per unit area of the radiations,
$P = pv$
$\Rightarrow \ \ \ \ \ \ \ \ \ \ p = \ \frac{P}{v}$
$= \ \frac{0.5}{3\ \times \ 10^{8}}\ = \ 0.166\ \times \ 10^{- 8}\ {Nm}^{- 2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.