Source of sound is 30 cm from the first listener A's ear and 1.50 m from the second
listener B's ear. What is the difference between the sound intensity levels heard by the two listeners,
knowing that the sound intensity is inversely proportional to the square of the distance from the source to
the listener?

Listener B will experience lower intensity of 5/2 I compared to the initial value where I is intensity.

Explanation:

Sound intensity decreases inversely proportional to the distance squared.This means sound intensity decreases with distance with a value of 1/r² from the source of sound.Averagely when the distance is twice, the sound intensity is reduced to 1/4 of its initial value.

if 2r= 1/4 I  where r is distance from source of sound and I is intensity

then for the case of 150/30 = 5 times

2r = 1/4 I

5r = ? cross- product

5/2 I the intensity will be reduced to this value for the distance of 150 cm

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