calculus help?

Question

A stone is dropped from the edge of a roof, and hits the ground with a velocity of -175 feet per second. How high (in feet) is the roof?

Answer 1

This is really a physics question, and a fairly artificial one at that (assumes uniform acceleration, no air resistance, et cetera).

2 g h = v² so h = v² / 2g

where g is the acceleration of gravity ( 32 ft / s² ), h is the height of the roof, and v the final velocity ( 175 ft / sec ).