Problem 4.163

A point isotropic source with sonic power $P=0.10 \mathrm{~W}$ is located at the centre of a round hollow cylinder with radius $R$ $=1.0 \mathrm{~m}$ and height $h=2.0 \mathrm{~m}$. Assuming the sound to be completely absorbed by the walls of the cylinder, find the mean energy flow reaching the lateral surface of the cylinder.