Question

A surface receiving sound is moved from its original position to a position three times farther away from the source of the sound. The intensity of the received sound thus becomes

A. three times as low.
B. nine times as high.
C. three times as high.
D. nine times as low.

Answer 1

Correct answer choice is :

B) Nine times as high.

Step-by-step explanation:

Sound intensity level also identified as acoustic intensity is described as the energy taken by sound waves per unit area in a path perpendicular to that area. The SI unit of intensity, which involves sound intensity, is the watt per square meter (W/m2). The loudness of a sound describes the intensity of any given sound to the intensity at the start of sound. It is marked in decibels (dB).

Answer 2

Intensity follows inverse square law.

That is the intensity varies inversely as the square of the distance from the source.

So if it is moved three times farther away, the intensity would be 3² less

= 9 times as low.

B.