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It’s the age-old question. What’s going to get you less wet, sprinting through the rain or walking normally? There are a lot more factors involved than you might have thought, but physics dictates that running as fast as possible will normally keep you drier, unless there’s a tailwind, or, err, you’re a bit thin.
Professor Franco Bocci, from the University of Brescia in Italy, worked out that it all relies on your height-to-breadth ratio, or in other words, whether you’re a bit porky or not. If you’re a bit on the skinny side there’ll be an optimum pace, but for everyone else, running as fast as you can will keep you drier, save for puddle splashing of course.
The maths, as you might expect, is pretty complex, and the whole problem is complicated by wind speed and direction too. If, for instance, the wind is blowing from behind you, the optimum running speed will be the same as the wind speed. That’ll probably be quite difficult to work out, unless you’re carrying one of those windspeed meters attached to your phone, of course.
So, there you have it. Sprinting will keep you the driest; although, frankly, if it’s raining, the best way to keep dry is to get in the car, train or bus. Or get yourself one of those charging umbrellas, I guess. [IOP via BBC]
Image credit: Raining from Shutterstock
Thanks Udimion!
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There’s a Morning Coffee Physics page dedicated to this very issue, including simple maths that even I can understand.
http://morningcoffeephysics.com/running-in-the-rain/
While I’d say if you went into a lot of detail the maths is pretty hard, but we were given a problem like this last year (as 2nd year engineering students) and we were able to draw the same conclusions from relatively basic principles…
Sprinting as fast as you can, I think they missed a variable, the likelihood of slipping up and falling into a very wet puddle, I’ll stick to just using an umbrella.
The Mythbusters did this with actual running in the rain and measurements, not theory or math.
They found out that running through the rain makes you wetter.
Mythbusters revisited this in a later series. This time they did the experiment in actual rain rather than in artificial conditions and found the reverse to be true.
In fact, the Mythbusters results are covered in the link that Swist posted.