In the 1960s, thanks mainly to MIT mechanical-engineering professor Ascher Shapiro ’38, PhD ’46, the world became captivated by the question of how a bathtub drains. Harold Edgerton captured this side ...

Open the plug in a sink or bathtub and watch the water drain. Usually, the water will begin to swirl and sometimes it forms a vortex, a sort of a non-violent tornado. This vortex is a result of ...

PERENNIALLY one hears controversy regarding the direction of the vortex in the drain of the bath-tub or the kitchen sink. Some claim that the direction of swirl is always the same in the northern ...

Water swirling down a drain has exposed an elusive phenomenon long believed to appear in black holes. Light waves scattering off a rotating black hole can bounce off with more energy than they came in ...