Silvas McEvil pushes a safe off the top of a building 200 meters tall. How much time does his victim on the ground below have to move out of harm's way? At what velocity will the safe hit the ground?

Given: h = 200 m; g = 9.81 m/s^2 - gravity acceleration.

Find: t, v.

Use the formula h = gt^2 => t = sqrt{2 h/g} = sqrt{2 * 200 / 9.81} = 6.39 s - the time to move out if the size of the safe and its possible further 'jumps' are disregarded.

The final velocity is v = gt = sqrt{2g h} = 62.6 m/s.