d = 0.5g*t^2 = 122.5 m.
4.9t^2 = 122.5
t^2 = 25
t = 5 s. = Fall time.
d = r*t = 122.5 m.
343t = 122.5
t = 0.357 s.
T = 5 + 0.357 = 5.357 s.
Carol drops a stone into a mineshaft 122.5m deep. Calculate the time from when she hears it hit the bottom of the shaft. Assume the speed of sound in the air 343 m/s.
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