Party hearing. As the number of people at a party increases, you must raise your
ID: 1872747 • Letter: P
Question
Party hearing. As the number of people at a party increases, you must raise your volce for a listener to hear you against the background nolse of the other partygoers. However once you reach the level of yelling, the only way you can be heard is if you move doser to your listener, to the isteners personal space. Model the situation by repladng yo 11th an isotropic point source o fixed power p and replacing your listener with a p nt that absorbs part of your sound waves. These points are in a y separated by 1.60 m noise increases by -5.40 dB, the sound level at your listener must also increase. what separation r, is then required? replading erease. what se If the background Units me tolerance +/-2%Explanation / Answer
Given,
delta-B = 5.4 dB ; r1 = 1.6 m
We need to find r2
delta-B = B2 - B1
10 log(I2/I0) - 10 log (I1/I0) = 5.4 dB
10 log (I2/I1) = 5.4 dB
log(I2/I1) = 5.4/10 = 0.54
I2/I1 = 10^0.54 = 3.47
I = P/A = P/4 pi r^2
P/4 pi r2^2 x 4 pi r1^2/P = 3.47
r1^2/r2^2 = 3.47
r2 = sqrt (r1^2/3.47) = sqrt (1.6^2/3.47) = 0.85 m
Hence, r2 = rf = 0.85 m