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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
Intensity change in decibel
`=10 "log"(I_(2))/(I_(1))=20rArr "log"(I_(2))/(I_(1))=2rArr(I_(2))/(I_(1))=10^(2)=100`
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