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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
`dB=10"log"(I_(2))/(I_(1))rArr 20=10"log"(I_(2))/(I_(1))`
`rArr I_(2)=100I_(1)`
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ALLEN -WAVES AND OSCILLATIONS-Part-1(Exercise-01)
  1. A cylindrical tube, open at both ends, has a fundamental frequency f i...

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  2. An organ pipe P(1) open at one end vibrating in its first harmonic and...

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  3. An open pipe is suddenly closed at one end with the result that the fr...

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  4. The maximum length of a closed pipe that would produce a just audible ...

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  5. A cylindrical tube (L = 120 cm) is in resonance with in tuning fork of...

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  6. A closed organ pipe of radius r(1) and an open organ pipe of radius r(...

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  7. Plane sound waves of wavelength 0.12 m are incident on two narrow slit...

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  8. Two vibrating tuning forks produce progressive waves given by y, y (1)...

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  9. Frequency of tuning fork A is 256 Hz. It produces 4 beats/second with ...

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  10. Length of a sonometer wire is either 95 cm or 100 cm. In both the case...

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  11. Two open pipes of length 25 cm and 25.5 cm produced 0.1 beat/second. T...

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  12. 16 tuning forks are arranged in increasing order of frequency. Any two...

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  13. Two tuning forks having frequency 256 Hz (A) and 262 Hz (B) tuning for...

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  14. Two open pipes of length L are vibrated simultaneously. If length of o...

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  15. (a) The power of sound from the speaker of a radio is 20 mW. By turnin...

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  16. A sound absorber attenuates the sound level by 20 dB. The intensity de...

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  17. A whistle giving out 450 H(Z) approaches a stationary observer at a sp...

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  18. A person observes a change of 2.5 % in frequency of sound of horn of a...

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  19. Two trains A and B are moving in the same direction with velocities 30...

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  20. A whistle revolves in a circle with an angular speed of 20 rad//sec us...

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