The sound level at a point P is 14 db below the sound level at a point 1.0 m from a point source.Assuming the intensity from a point source drops off like the inverse square of the distance, the distance from the source to point P is:
A)4.0 cm
B)20 m
C)2.0 m
D)5.0 m
E)25 m

Question

Quizplus · Accepted Answer

The sound intensity level difference of 14 dB corresponds to an intensity ratio of 10^(14/10) = 25. Since intensity drops off with the square of the distance, the distance ratio is √25 = 5. Therefore, the distance from the source to point P is 5 times 1.0 m, which is 5.0 m.

The Sound Level at a Point P Is 14 Db