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149. Problem 20.34 (RHK) The reverberation time of an
auditorium or concert hall is the time required for the sound intensity (in
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) to
decrease by a factor of
.
Suppose that in a particular concert hall, the reverberation time for a note of
a certain frequency is 2.6 The reverberation time depends on the
frequency of the sound. If the note is sounded at a sound level of 87
dB, how long will it take for the sound level to fall to 0 dB.|
Solution: Click For PDF Version The intensity of sound of 87 dB can be calculated from the definition of sound level, SL, which is defined by the formula
For SL = 87 dB, I will be
It is given that the intensity of sound of a particular frequency in a
concert hall drops by a factor of
The time required for the sound level to drop down from 87dB to 0 can be estimated as follows:
The time required for the sound of 87 dB to 0 dB will therefore be
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in 2.6 s.
If the intensity has to drop to SL of zero it means that the intensity
should drop down to
.
