Question

a key falls from a bridge that is 45 m above the water. it falls directly into a model boat, moving with constant velocity, that is 12 m from the point of impact when the key is released. what is the speed of the boat?

Answer 1

H = 1/2 g t^2 time t for an object to fall a distance H

t = (2 H / g)^1/2 = (2 * 45 / 9.80)^1/2 = 3.03 sec for the key to fall 45 m

V = 12 m / 3.03 m/s = 3.96 m/s