Question

A rock is dropped from a hotel and strikes the ground with a particular speed. In order, to double the speed at impact, you would have to drop the rock from the hotel at?


I say impossible to determine

Answer 1

Yoy would have to from the rock from four times the height to get twice the velocity at impact (neglecting air friction). That is because kinetic energy in proportional to V^2. You'd need four times the kinetic energy, and that comes from four times the height (and potential energy)