Transporting a round of beers from the bar to your table is an achievable task, but you probably wouldn't want to carry three cups of coffee without lids. Scientists at Princeton and NYU are explaining why: When it comes to beer, we have the bubbles to thank, the Smithsonian reports. Using high-speed cameras, the researchers recorded motion on the surface of several drinks: coffee, amber beer, and Guinness. Foam reduced sloshing, and the experts say it's because the foam absorbs the energy of the moving liquid.
More foam meant less sloshing. That means that if you're looking for an easy-to-carry beer, Guinness may be your best bet. Why, you ask, are scientists spending their time on this? Well, it's not just to have a better night out. The study, an abstract says, "has promising applications in numerous industrial applications such as the transport of liquid in cargoes." And believe it or not, this isn't the first time the physics of coffee spillage has received study, Physics Central reports: A couple of years ago, "blurry-eyed physicists" tried to figure out how to walk with a full cup of coffee without spilling any, as the American Physical Society noted. (Some of us respond very inappropriately when our beer is spilled.)