Suppose that a public address system emits sound uniformly in all directions and that there are no reflections. The intensity at a location 27 m away from the sound source is 3.0 × 10-4 #W/m^2#. What is the intensity at a spot that is 87 m away?
I have assumed that the inverse square law is followed here:
For the 1st case we can write:
For the 2nd case: