Chapter 0.4, Problem 68E

Sound intensity The intensty of sound $I$

(as a multiple of the average minimum threshold of hearing intensity) is related to the decible level D ( or loudness of sound) according to

$I={10}^{\frac{D}{10}}$

(a) Express ${10}^{\frac{D}{10}}$ using radical ntation.

(b) The back ground noise level of a relatively quite room has a decibel reading of 32.Find the intensity $I_1$ of this noise level.

(c) Adecibel reading of 140 is at the threshold of pain if $I_2$ is the intensity of this threshold and $I_1$ is the intensity found in part (b), express the ratio $\frac{I_2}{I_1}$ as a power of 10.Then approximate this ratio.