Question

The sound intensity at 4 m from a source is 100 W/me. What is the intensity of the sound at 12 m away from the source ?

Answer 1

Intensity at 12 meters will be 11.11 W/m^2

Step-by-step explanation:

Recall that the intensity of sound is inversely proportional to the square of the distance from the source. Therefore, if at 4 m the intensity is 100 W/m^2

we have: 100 W/m^2 = k/16 and therefore, k = 1600 W

Then the intensity (I) at 12 m will be:

I = k/12^2 = 1600/144 W/m^2 = 11.11 W/m^2