Ganesh Ujwal

When a drop of water falls into a reservoir of water from a high enough altitude, water droplets will splash



My question: Does the water in those droplets come from the original drop or from the reservoir?

MATHEMATICIAN

reservoir

v8archie

When the drop enters the water it pushes water in the reservoir out of it's way (this action uses up the energy of the drop, causing it to slow down and stop). When the drop has passed it leaves air behind it (a slip-stream effect). The reservoir water bordering this slipstream then moves from all sides to fill in the gap. When the water from opposite sides meet in the middle it must dissipate the energy in the collision. It cannot move to the sides or down, because there is water already there, so it 'bounces' up instead.

In your picture, one can see the original drop at the bottom of the disturbed water and the 'slipstream' above it.