The howler monkey is the loudest land animal and can be heard up to a distance of 2.5 km.Assume the acoustic output of a howler to be uniform in all directions.The acoustic power emitted by the howler,in mW,is closest to:

Question

Quizplus · Accepted Answer

The intensity of sound decreases with the square of the distance from the source. So, the intensity at a distance of 2.5 km is 1/(2.5)^2 = 0.16 times the intensity at a distance of 1 m. The acoustic power is proportional to the intensity, so the acoustic power at a distance of 2.5 km is 0.16 times the acoustic power at a distance of 1 m. The acoustic power at a distance of 1 m is given as 0.5 mW, so the acoustic power at a distance of 2.5 km is 0.5 mW * 0.16 = 0.08 mW. The closest choice to this value is 0.079 mW.

The Howler Monkey Is the Loudest Land Animal and Can