Airplanes are noisy things. For example, if you stand really close to a runway, a military jet can produce a sound intensity of about 100 W/m^2 at a distance of 30 m from the plane (this is beyond painful noise). You live near a military airport and want to work on physics with your friend. Since you don't want to shout, you decide to find a spot far enough away from the airport that the airplane noise is below the threshold of conversation (10^{-6} W/m^2). How far do you need to go from the airport in kilometers to accomplish this?
3 answers
300
precisely 299.99999999 by the formula I=P/r(pi)r^2 .
Thank you for the answer.
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