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A point source emits sound equally in all directions in a non–absorbing medium. Two points P and Q are at distances of 2 m and 3 m respectively from the source. The ratio of the intensities of the waves at P and Q is
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- 3 : 2
- 2 : 3
- 9 : 4
- 4 : 9
Correct Option: C
Intensity = Energy/sec/unit area
Area ∝ r² ⇒ I ∝ 1/r²
| ⇒ | = | = | = | ||||
| l2 | r1² | 2² | 4 |
