physics
posted by Anonymous on .
April releases a rock at rest from the top of a 40 m tower. Ignoring air resistance, what is the speed of the rock as it hits the ground? ( g = 9.8 m/s/s)

Calculate how long it take to hit the ground, by rearranging the equation
Y = (1/2) g t^2
which should be in your course/text materials.
Let Y be the 40 m distance that it falls. Solve for t.
on ce you have t, get the velocity from
V = gt