Researchers are a step closer to understanding the science behind one of life’s common pitfalls – spilling coffee.

Scientists from the University of California, Santa Barbara, decided to investigate the physics behind the best way of carrying coffee without causing spillages.

‘In our busy lives, almost all of us have to walk with a cup of coffee. While often we spill the drink, this familiar phenomenon has never been explored systematically,’ the abstract of the paper entitled ‘Walking with coffee: Why does it spill?’ states.

‘Here we report on the results of an experimental study of the conditions under which coffee spills for various walking speeds and initial liquid levels in the cup.’ Rouslan Krechetnikov, a mechanical engineer at the university, and his graduate student, Hans Mayer, explored the phenomenon by conducting a series of experiments.

They monitored a person walking at different speeds along a straight path while holding a full mug of coffee and either focusing on the mug, or looking straight ahead. A camera recorded the volunteer’s motion, while a tiny sensor on the mug recorded the instant of spillage, according to ScienceNOW.

The research, published in the journal Physical Review E, found that in average sized mugs the coffee’s natural frequency was the same as a person’s gait, which caused the liquid to oscillate. 

The spillages were most likely between a coffee carrier’s seventh and tenth step, according to Live Science.

Following their discovery, the mechanical engineers had some advice for coffee drinkers.They said leaving a large gap between the coffee and the top of the drinking vessel, and walking slower, prevents spillages. 

They added that watching the mug, rather than the floor, while carrying it proved to be a more effective coffee-holding method.

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