Nowadays I hardly comment on my games: But my game runs on Newton's theory and the Law of Relativity. The game is run in a vacuum, therefore there's no air resistance+anything has restitution, throw a metal ball on the ground, it bounces.
Jesus Christ, all of you sound like 16 year olds :
Have any of you heard of restitution? Try throwing your heads on the ground : Hard. It should bounce of the ground before you notice it.
Likewise place a balloon on water. now press it down. Then suddenly release it, doesn't it shoot upwards? Same here: gravity pushes an object downwards, and when it's released it shoots up! But gently... And it continues moving up because now there's no force stopping it!