A rocket in a fireworks display explodes high in the air. The sound spreads out uniformly in all directions. The intensity of the sound is 2.0 *10^-6 W/m^2 at a distance of 120 m from the explosion. Find the distance from the source at which the intensity is 0.80 *10^-6 W/m^2.
Basically, the sound energy will be distributed on the surface of a sphere that expands outwards from the rocket. Ignoring any loss of sound energy (due to heating, etc), we can say that the intensity is inversely proportional to the surface area of the ...
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