A more important consideration is how symmetrical the splash is. A nice, round stone falling straight into flat, deep water is likely to push the water away, leaving a fairly clean circlular hollow. The water then floods back symmetrically in such a way that it all reaches the centre from all sides at once. The result is that the bit in the middle gets squeezed together with a loud slap, and squirts upward at high speed, taking a large part of the energy with it. Quite a small amount of water then gets lifted with a large part of the energy that the falling stone delivered. That water may sometimes rise far higher than the height the stone fell from.
Even a slight deviation from symmetry can prevent the effect. Instead there is a messy slosh in any old direction, and no impressive splash. Or the stone might be of such a shape that it does not cause the right shape of hollow in the water.
Sometimes one gets the same effect when a small amount of liquid gets dropped into water. Then often the liquid that splashes up is the liquid that got dropped. One can see this most clearly when a teaspoonful of milk say, drops neatly into a cup of tea, and what splashes out is practically pure milk.
Sometimes a high-speed photo will demonstrate the effects very impressively.
Think about experimenting with cameras and splashes and flashes. People sometimes get fabulous shots that way.
Jon
