<PRE><B>Question 1187331</B>
If the rock is dropped from the second floo which has a height of 128ft, a) how long will it take to fall half the distance to the ground? b) how long will it take to fall to the ground?
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128 feet is unusual for 2 stories.
Using 32 ft/sec/sec for gravity:
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a) how long will it take to fall half the distance to the ground?
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s = at^2/2 = 64 ft
16t^2 = 64
t = 2 seconds
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 b) how long will it take to fall to the ground?
s = at^2/2 = 128 ft
16t^2 = 128
t^2 = 8
{{{t = 2sqrt(2)}}} seconds</PRE>