(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

You are at a rock concert, standing 12.1 m from one of the loudspeakers. Based on the pain in your ears, you estimate the decibel level to be about 112 dB at this location. You are worried that this intensity level may be harmful to your ears and result in a degradation of your hearing in years to come, so you want to move farther away from the loudspeaker to reduce the sound to a "dull roar" at a decibel level of 89 dB. From your present location, how much farther away from the loudspeaker would you have to move to reach this reduced decibel level?

2. Relevant equations

B = 10log(I/I(0))

P = I(4pi*r^2)

3. The attempt at a solution

I have a solution, but want to make sure I'm not going down the wrong path.

First, I calculated the Intensity for 112dB and 89 dB and got 0.158 and 7.94e-4, respectively. Then, I calculated the Power using the given distance and first intensity and got 290.7W. Then, I used that Power and the 2nd intensity to solve for r.

Does this look like the right method? Thank you.

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# Homework Help: Decibels and distance

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