The Bartender and the Barista: How Physics Makes Beer Easier to Carry than Coffee

Anyone who has ever carried a tray full of pint glasses without getting their feet wet knows that such a feat is hard work, but perhaps our sympathies should go out to the baristas in coffee shops instead. New research has concluded that carrying coffee without spilling is harder than beer since the foam on the surface of beer dampens sloshing.

A team of physicists at Princeton and NYU Polytechnic School of Engineering set up an experiment which jolts three identical pint glasses carrying Guinness, Heineken, and black coffee, and measures the resulting oscillations.