(adsbygoogle = window.adsbygoogle || []).push({}); Sound Intensity-- just need someone to check my work :)

1. The problem statement, all variables and given/known data

While enjoyable, rock concerts can damage people's hearing. In the front row at a rock concert, 5m from the speaker system, the sound intensity is 145 dB. How far back would you have to sit for the sound intensity to drop below the recommended safe level of 90 dB?

2. Relevant equations

[itex]\Delta[/itex]B=10 log(I1/I2)

I1/I2=r2^2/r1^2, so [itex]\Delta[/itex]B = 20 log (r2/r1)

3. The attempt at a solution

Plugging into the above equation yields (145-90) = 20 log (r2/5)

Rearranging, r2 = 5*10^[(145-90)/20] = 2812 m. I don't know where I could've made a mistake-- this is a pretty straightforward problem-- but that answer seems unreasonable.

Does it look alright to you?

Thanks!

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# Homework Help: Sound Intensity- just need someone to check my work

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