Q 12-08-023NEETJEE MainTop questionMedium
An EM wave of intensity $6\ \text{W/cm}^2$ falls normally on a perfectly reflecting surface. The radiation pressure on it is
Answer: (D) $4 \times 10^{-4}$ Pa
$I = 6 \times 10^4\ \text{W/m}^2$. For perfect reflection $P = \dfrac{2I}{c} = \dfrac{1.2 \times 10^5}{3 \times 10^8} = 4 \times 10^{-4}$ Pa. (Half this for a perfect absorber.)
Solution by Sreeraj P, M.Sc Physics