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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)=10 log .(I_(t))/(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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