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A sound absorber attenuates the sound le...

A sound absorber attenuates the sound level by 20 dB. The intensity decreases by a factor of :

A

`1000`

B

`10000`

C

`10`

D

`100`

Text Solution

Verified by Experts

The correct Answer is:
D
`beta_(1) = 100log'(I_(1))/(I_(0)) , beta_(2) = 10 log'(I_(2))/(I_(0))`
`beta_(1) - beta_(2) = 10 log'(I_(1))/(I_(2)) = 20`
`log'(I_(1))/(I_(2)) = 2 rArr (I_(1))/(I_(2)) = 100`
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RESONANCE ENGLISH-SOUND WAVES-Exercise- 3 PART - I
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