physics

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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?

• physics -

vf^2=2*g*height

• physics -

so its 2*9.81*155?

• physics -

K.E. = P.E.
1/2mv^2 = mgh
v^2 = 2gh
v = (2gh)^(1/2)
v = (2x9.81x155)^(1/2)
v = 55.146m/s

• physics -

OH!! so that's where i went wrong. thanks again! ^w^

• physics -

lol, you are welcome

• physics -

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

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