- #1
Rorshach
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Homework Statement
Hello. I have a problem, which is as follows:
A seat in a concert hall is 84 ft from the tympani. The tympanist strikesa single note. The sound pressure level of the direct sound of the note at the seat is measured to be 55 dB. The first reflection from the nearest sidewall arrives at the seat 105 msec after the arrival of the direct sound.
A) How far does the reflection travel to reach the seat?
B) What is the SPL of the reflection at the seat, assuming perfect reflection at the wall?
C) How long will the reflection be delayed after arrival of the direct sound at the seat?
Homework Equations
sound speed in air:
1130 ft/sec
SPL=20log(p/pref)
The Attempt at a Solution
The thing is, they are all solved in the book right under the data, but I don't understand anything beyond the first question and its solution. I would like to ask for some explanation on how why this is solved in this particular way.
First one is easy, I got this:
A)distance=(1130ft/sec)(0.105 sec)=118.7 ft
Please help me understand the other two questions.
Solutions to the are:
B)52 dB
C)30.7 msec
So far point C) is most confusing to me, isn't the answer given in the problem(105 msec)?