Question

A stone is dropped from the edge of a roof, and hits the ground with a velocity of −170 feet per second. Assume the acceleration due to gravity is -32 feet per second squared. How high (in feet) is the roof?

I have found s which is 16^2 but I do not know what formula to use.

Answer 1

distance = -16t^2 + h
velocity = -32t
but we know that is -170

so -32t = -170
t = 85/16 seconds

so how far his it fallen in 85/16 seconds?

distance = 16(85/16)^2
= 7225/16 ft or
appr 451.56 ft