... This appartus will drop a mass from different heights. When the mass strikes the ground, some percentage of its original energy will be absorbed by the ground. ... The percentage of the energy which is absorbed by the surface on each "bounce" (EAS) . ... The impact velocity of the object will also be given at each bounce. ... Start= Drop the ball after Energy, Mass and EAS have been set; resume after step or pause has been selected . ... Reset = Reset experiment to intial values . ...