I have no idea what I'm doing wrong on this one. I'm having problems somewhere in the log conversions to W/m^2 I believe.(adsbygoogle = window.adsbygoogle || []).push({});

A siren mounted on the top of towers produces a noise of 120 dB at a distance of 2 meters. Treating the siren as a point particle (and ignoreing reflection and absorbtion) find the intensity level heard by an observer (a) 12 m away (b) 21 m away. (c) How far away can the sound be heard?

First I thought this was going to be an easy plug in the formula problem. Where I2=(r1/r2)^2 *I1

I think I need to convert this to W/m^2, and then plug it into this equation, and then convert back. However, I'm not quite sure how to do this. I think it has something to do with Β=10 log (I/Io) Where Io is 10^-12 W/m^2

So we have B=1200 (thats 120 dB times 10)

120=10 Log (I/(10^-12)) Can you help me solve this one? Thanks a million!

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# Homework Help: Sound Intensity problem. Need some help.

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