Question

The $SI$ unit of intensity of wave is

• A. $W{m}^2$
• B. $J{m}^{-1}{s}^{-2}$
• C. $W{m}^{-2}$
• D. $J{m}^{-2}S$

Answer 1

Answer: (C)

Intensity of wave $=\frac{\text{Energy}}{\text{Area × Time}}$
$=\frac{J}{m^2\times s}=W{m}^{-2}$
$\therefore$ The $SI$ unit of intensity of wave is $W{m}^{-2}$.