﻿ A certain amount of acoustic energy is emitted in a uniform hemispherical pattern from a point source. At a distance of 5 m form the source the intensity is 5 W/m2. At a distance of 15 m the intensity will be: : Kaysons Education

# A Certain Amount Of Acoustic Energy Is Emitted In A Uniform Hemispherical Pattern From A Point Source. At A Distance Of 5 M Form The Source The Intensity Is 5 W/m2. At A Distance Of 15 M The Intensity Will Be:

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## Question

### Solution

Correct option is

The energy is emitted uniformly over a hemisphere whose surface area is 2πr2

Since no energy leaks out from the sides of this growing hemisphere we may equate the total energies for any value of r

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