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A person is talking in a small room and ...

A person is talking in a small room and the sound intensity level is 60dB everywhere within the room. If there ar eight people talking simultaneously in the room, what is the sound intensity level?

A

60 dB

B

69 dB

C

74 dB

D

81 dB

Text Solution

Verified by Experts

The correct Answer is:
B
Let intensity due to a single person =I
then `10 log I//I_(0)=60`
Also, intensity due to 8 person =8L
`:.` final decibal level
`=10 log((8I)/(I_(0)))=10(log.(I)/(I_(0))+log8)`
`=60+10 log 8=60 +30 log2=60+30(.3010)`
`=69`
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RESONANCE ENGLISH-SOUND WAVES-Exercise- 3 PART - I
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