Question

The velocity of a sound wave in $v$ and the wave energy density is $E,$ then the amount of energy transferred per unit area per second by the wave in a direction normal to the wave propagation is

• A. $E$
• B. $Ev$
• C. $E^2{v}^2$
• D. $\sqrt{Ev}$

Answer 1

The correct option is B $Ev$

Energy transferred in normal direction to the wave propogation is also known as intensity

$I=\frac{1}{2}\rho a^2{\omega }^{2}v$

$E={\omega }^2{a}^2\rho$

hence $I=Ev$