A firework charge is detonated many meters above the ground. At a distance of 400 m from the explosion, the acoustic pressure reaches a maximum of 10.0 N/m(adsbygoogle = window.adsbygoogle || []).push({}); ^{2}. Assume that the speed of sound is constant at 343 m/s throughout the atmosphere over the region considered, that the ground absorbs all the sound falling on it, and that the air absorbs sound energy as described by the rate 7.00 dB/km. What is the sound level (in dB) at 4.00 km from the explosion?

I've been on this question for a while...can't seem to get the answer. The answer I'm supposed to get is 65.6 dB.

Since the sound wave seems as though it'd be a spherical wave, the area in the equation for power and the area the power is distributed over (in the intensity equation) are different...so they do not cancel out. From what I understand from the question, some of the sound energy is being absorbed by the air to produce the drop of 7.00 dB/km...which will cause the drop in intensity over a distance to be higher than with it simply decreasing due to distance alone. What would I do from here?

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# Homework Help: Sound Waves from firework

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