Ive been trying this one for a little while now and keep getting myself stumped here... So the question is...(adsbygoogle = window.adsbygoogle || []).push({});

A person sees a heavy stone strike the concrete pavement. A moment later two sounds are heard from the impact: one travels in air and the other in the concrete, and they are 1.4 s apart. How far away did the impact occur? (the speed of sound in concrete is about 4000 m/s)

So far I've got...

VConcrete = 4000m/s

VAir = 349 m/s

I've come up with a model that basically has 3 variables...

D1 = total distance

D2 = distance from rock hitting ground to 1.4s mark

D3 = 1.4s mark to person

Ive found that

Dconcrete = 4000*1.4 = 5600m

Dair = 349*1.4 = 488.6m

So I need to find D2 and D3 Lengths using the above somehow , D3 takes 1.4s for the slower sound, which would be the sound moving through the air.

d3 = 1.4s D2 =?

Person l______________l_________Rock

l_______________________l

D1 = total disance

My diagram got screwed by autoformatting.. everything is shifted to the right

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# Homework Help: Help on Sound problem

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