Question

A sound wave radiates with 8.5X10^-5W of power. What is the intensity of the sound wave at a distance of .015 meters

Answer 1

$$I=\frac{P}{A}=\frac{P}{4\pi R^2}\\I=\frac{8.5\cdot10^{-5}}{4\pi (0.015)^2}=0.03\frac{W}{m^2}$$