Mechanical energy = potential energy + kinetic energy
The ball is on the ground so it has no potential energy. that's all i know.
The ratio of the distance moved by the point at which the effort is applied in a simple machine to the distance moved by the point at which the load is applied, in the same time. In the case of an ideal (frictionless and weightless) machine, velocity ratio = mechanical advantage. Velocity ratio is sometimes called distance ratio.
When your hand hits the table the table will vibrate and your hand will be numb for two to three seconds
