Q18 of 118 Page 352

The intensity of sound from a point source is 1.0 × 10-8 W m-2 at a distance of 50 m from the source. What will be the intensity at a distance of 25 m from the source?

Given:
The intensity =, when the distance of the point source


= 5 m.
Let be the intensity of the point source at a distance


As we know,



So,


⇒


On substituting the respective values, we get:




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