Foam stops sloshing liquid: Analysis reveals capillary effects that dampen sloshing

Clinking your glass of beer often leaves its contents sloshing back and forth. Soon, though, the motion stops, your drink settles, and you can sip without getting foam on your nose. The foam helps stop the sloshing, and now, physicists have figured out why. The analysis reveals a surprising effect on the surface of the water that contradicts conventional thought and deepens our understanding of the role of capillary forces.