A howler monkey is the loudest land animal and,under some circumstances,can be heard up to a distance of 5.0 km.Assume the acoustic output of a howler to be uniform in all directions and that the threshold of hearing is 1.0 × 10^-12 W/m².The acoustic power emitted by the howler is closest to A)0.31 mW. B)0.11 mW. C)1.1 mW. D)3.2 mW. E)11 mW.

Question

Quizplus · Accepted Answer

The intensity at the threshold of hearing is 1.0 × 10^-12 W/m². At a distance of 5.0 km, the surface area of the sphere is 4π(5000)² m². The power is intensity times area: P = I × A = 1.0 × 10^-12 W/m² × 4π(5000)² m² ≈ 0.31 mW.

A Howler Monkey Is the Loudest Land Animal And,under Some