THE TUNING OF A SPLASH

A water drop falling into a shallow pool of water can give rise to a splash that ejects droplet fragments high into the air. The height reached by the highest-flying ejected droplet is greatest when the depth of the target liquid is equal to the radius of the hemispherical crater formed by the impact of the incident drop. This phenomenon, referred to here as the tuning of a splash, is still observed when liquids of very different viscosity and surface tension are substituted for water, but a thin sponge layer cemented over the floor of the pan all but destroys the tuning behavior. Cine images reveal a possible explanation for the tuning phenomenon based on a delay of the upward retraction of the collapsing crater. © 1990 American Institute of Physics.