so im kind of stumped on this one here.... A rock is dropped from a sea cliff and the sound of it striking the ocrean is heard 3.4 seconds later. If the speed of sound is 340m/s, how high is the cliff?(adsbygoogle = window.adsbygoogle || []).push({});

- now i got some variables, v1=0 m/s

time(total)=3.4s

a= -9.80m/s^2

delta d= ?

i got thinking that the total time it takes for the rock to fall then the sound to come back at you would be 3.4 seconds in total, so i dont know how to seperate the time it takes the rock to fall from the time it takes the sound to actually get back to you.

by using the 3.4 seconds, i tried to get a distance which was off, at 113 m, but then realized that i need to find out how long it takes for the rock alone to fall, without the sound. i cant find a reasonable way to get this number.

please help!?

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# Homework Help: Kinematics, rock falling off cliff

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