Question

A woman stands a distance d from a loud motor that emits sound uniformly in all directions. The sound intensity at her position is an uncomfortable 3.3×10^-3 W/m². At a distance 2.9 times as far from the motor, what are (a) the sound intensity and (b) the sound intensity level relative to the threshold of hearing?

Answer 1

Given is:-

Initial uncomfortable sound intensity at distace d is =

now we have to found the intensity at distance 2.9 times of original distance

therfore

the sound intensities with compare to distances is given by

by putting all the values in above equation, we get

   (Part-a)

Now for sound intensity

The sound intensity level relative to the threshold of hearing

thus the intensity of sound at 2.9 times of initial distance in decibles is 85.39db