Question

A sound point source, situated 2.5 m above a brick floor, is
emitting sound at 5 ✕ 10^{−5} watts.

(a) Find the sound intensity level (in dB) due to that source at a listening point 3.9 m above the floor and 17 m away. (Assume that 17 m is the horizontal distance between the sound point source and the listening point. Do not take reflection from the floor into account.)

=? dB

(b) Find the sound intensity level (in dB) at that point when the reflection from the floor is taken into account. (Assume 100% reflection.)

=? dB

Answer #1

A sound point source, situated 1.8 m above a brick floor, is
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(a)
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14 m is the horizontal distance between the sound point source and
the listening point. Do not take reflection from the floor into
account.)
dB
(b)
Find the sound intensity level (in dB) at...

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I =
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SubmitPrevious Answers
Correct
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