How Do You Calculate the Power Emitted by a Sound Source?

AI Thread Summary
To calculate the power emitted by a sound source, the intensity (I) at a distance (r) can be used with the formula P = I(4πr^2). Given an intensity of 6.0x10^-10 W/m^2 at 6.0m, the power can be calculated as P = 6.0x10^-10 W/m^2 * 4π(6.0m)^2. This results in a power output of approximately 2.7x10^-7 W, which matches the provided answer. The discussion highlights confusion around the use of formulas and the need for clarity in problem-solving techniques. Understanding the relationship between intensity and power is crucial for solving such problems effectively.
Eternalmetal
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Homework Statement


The intensity at a distance of 6.0m from a source that is radiating equally in all directions is 6.0x10^-10 W/m^2. What is the power emitted by the source?

They give you multiple choice answers, and the answer is 2.7x10-7 W.



Homework Equations



I is proportional to 1/r^2.

B = 10log(I/10^-12)


The Attempt at a Solution



I don't really know how to approach getting the solution, I have tried working backwards from the solution and kind of got nowhere. I see no reason to use the decibel formula because there is no need to indicate loudness, so the only other formula I have to work with is a proportion. Could somebody please help me with the formulas/logic needed to solve this problem? I have a terrible professor and my book is no help. Thanks.
 
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Bump. I still need help with this, I put in a bunch of time and I am still lost. I would really appreciate a formula or concept explanation or anything, I have the answer but I just want to know how to do it.
 
I don't know but since u haven't got a reply I am just guessing..

there is some formula i can't remember it is something like...

I =p/4pieR^2


P= I(4)(pie)(r)^2 that gives u like 2.7 x 10 ^-6 W

so it might be wrong and i guess it is since u gave teh answer already but find the power formula and it should be as simple as plugging in..
 

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