Calculating Sound Energy from Isotropic Loudspeaker

AI Thread Summary
To calculate the sound energy produced by an isotropic loudspeaker, the sound level of 66 dB at a distance of 24 m must first be converted to Watts. The intensity of sound is related to the distance from the source, typically following an inverse square law where energy decreases with the square of the distance. The discussion highlights the need for a formula that incorporates distance to determine the rate of sound energy production. Participants are encouraged to reference their textbooks for relevant equations that include distance in their calculations. Understanding these principles is essential for solving the problem effectively.
Jtappan
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1. Homework Statement

The sound level 24 m from a loudspeaker is 66 dB. What is the rate at which sound energy is produced by the loudspeaker, assuming it to be an isotropic source?

____W

2. Homework Equations

?

Something to do with Intensity?

3. The Attempt at a Solution

I don't know where to begin on this problem. My book doesn't describe any problems that are related to distance nor does it have any equations that are related to distance.
 
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First, convert the 66dB to Watts. (http://en.wikipedia.org/wiki/Decibel) look in the example section if you don't know how to do that. This will give you the energy rate 24m away.

Next, you'll need to find some formula which relates how energy falls off with distance...any ideas? Look in your book for a formula with (distance)^2 in the denominator.
 

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