Calculate Intensity of Sound Waves at 3.0 m from Source

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The discussion revolves around calculating the intensity of sound waves emitted from a source with a power output of 80W at a distance of 3.0m, yielding an intensity of 0.71W/m² and an intensity level of 118.51 dB. A participant expresses difficulty in determining the distance at which the intensity would be one-fourth of the initial value, initially calculating it to be 7.173m. Others prompt the participant to verify their calculations, specifically questioning the values of pi and the radius used in the formula. The conversation emphasizes the importance of accurate arithmetic in solving physics problems. The thread highlights common challenges in applying formulas related to sound intensity and distance.
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Homework Statement


A small source emits sound waves with a power output 80W.
a) find the intensity at a point 3.0m from the source. (0.71W/m)
b) find the intensity level at the same point as part a.(118.51)
c) at what distance would the intensity be one-fourth as much as of that part (a).

i have no problem finding the answer for a and b, but i did have a bit of problem in c. i have tried to answer it which i get r=7.173, but i don't know is it right or wrong. help me for C.

2. Homework Equations c
B=10log(I/Io)
Ia=P/4pie r^2

The Attempt at a Solution


I=p/4pie R^2

i get 7.173 after calculate it.
 
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Check your arithmetic. How much is pi? How much is R? How much is 4 pi R^2?
 

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