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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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ALLEN -WAVES AND OSCILLATIONS-Part-1(Exercise-05)[A]
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  9. The transverse displacement y(x, t) of a wave on a string is given by ...

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  10. Statement-1: Two longitudinal waves given by equation y(1)(x,t)=2asin(...

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  11. A transverse wave travelling along the positive x-axis, given by y=A s...

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  12. A cylindrical tube, open at both ends, has a fundamental frequency f i...

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  13. A sonometer wire of length 1.5m is made of steel. The tension in it pr...

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  14. A pipe of length 85cm is closed from one end. Find the number of possi...

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  15. A train is moving on a straight track with speed 20 ms^(-1). It is blo...

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  16. A bat moving at 10 ms^(-1) towards a wall sends a sound signal of 8000...

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  17. A source of sound emits sound waves at frequency f(0). It is moving to...

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  18. A uniform string of length 20m is suspended from a rigid support. A sh...

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