When a drop of liquid hits a solid surface, the liquid will do one of two things: flatten like a pancake or launch a halo of droplets into the air. It’s a surprisingly complex and difficult-to-predict event.
The secret is in the air. By taking into account the gas surrounding the drop, researchers find that they can calculate just how fast a drop can travel without splattering when it hits. A new study suggests that after the drop strikes a solid surface, a tiny cushion of air carries along its edge as it spreads. The air provides lift like on an airplane wing and flings away droplets from the drop’s edge.
See videos below.