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Feb15-12, 06:22 PM   #1
 

Free Fall(gravity) with speed of sound in air


A pebble is dropped into a deep well, and 3.0s later the sound of a splash is heard as the pebble reaches the bottom of the well. The speed of sound in air is 340m/s.

(A) How long does it take for the pebble to hit the water?
(B) How long does it take for the sound to reach the observer?
(C) What is the depth of the well?

t=?
Initial Velocity=0
g=-9.8

I've used all of the formulas I have and still havent been able to figure out how to get this. Someone please help. (At least with A)

Formulas Given: d=.5(final velocity + initial velocity)t
d= initialvelocity(t) + .5at^2
final velocity^2= initialvelocity^2+ 2ad
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