Question

SI unit of intensity of wave is

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

Answer 1

Answer: (C)

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