physics
posted by Brittany .
The single cable supporting an unoccupied elevator breaks when the elevator is at rest at the top of a 155 m high building. With what speed does the elevator hit the ground?

vf^2=2*g*height

so its 2*9.81*155?

K.E. = P.E.
1/2mv^2 = mgh
v^2 = 2gh
v = (2gh)^(1/2)
v = (2x9.81x155)^(1/2)
v = 55.146m/s 
OH!! so that's where i went wrong. thanks again! ^w^

lol, you are welcome

but what if it asks how long it will take to fall?
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