Question

A point source of power $50\pi \text{watts}$ is producing sound waves. The velocity of sound is $330m/s$, density of air is $1.0kg{m}^{-3}$. Then at $r=\sqrt{330}m$ from the point source pressure amplitude ( in $N{m}^{-2}$) is. (Using $\pi =\frac{22}{7}$ )

Answer 1

As we know,

Intensity of sound wave,

$I=\frac{P}{4\pi r^2}=\frac{p_0^2}{2\rho \upsilon }$

$p_0^{\prime }=\sqrt{\frac{2\rho \upsilon P}{4\pi r^2}}=\sqrt{\frac{2\times 1\times 330\times 50\pi }{4\pi \times 330}}$

$=5N/m^2$

Final answer: (5)