(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A rock was dropped into a deep canyon and you hear the rock hit the bottom after 11.3 seconds.How deep is the canyon?

t=11.2s

velocity of sound is 340m/s in air

gravity is 9.8m/s/s

2. Relevant equations

i know that only two equations are involved in this problem, they are

d=vt

d=Vit+1/2at^2 (Vi is initial velocity, since Vi equal to 0 the equation is just d=1/2at^20)

3. The attempt at a solution

this is what i did:

(340m/s x 11.3s)/2=1921m

i think about this answer but this doesnt make any sense, according to my answer the rock must be travel at the speed of sound.

by the way i divided by 2 because the rock need 5.65( 11.3/2) to reach the bottome and another 5.65 seconds for the sound to reach your ears. Total of 11.3 seconds

please help, im stuck here

thank you a lot

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# Homework Help: Need help with this sound problem

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