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The Big Dilemma Everyone Faces

You leave the building to walk to your car...and find out that it is pouring rain, and you have no umbrella. If you run to your car, do you get less wet, more wet, and equally wet...compared to walking to your car?

People (and scientists) have argued over this tri-lemma for eons of time:

  • If you run, more of your body is exposed to more droplets of water in a unit of time, thus you get more wet...
  • If you run, your body will be exposed to the rain for less time, thus you will get less wet...
  • The two factors cancel each other (columnist Marilyn Vos Savant's position)....
An Italian physicist in 1987 offered data documenting that "if the distance is short enough, sprinting gets a person less wet than walking--but only by about 10%"...

A British researcher in 1995 used research data documenting that "it made no difference whether a person walked or sprinted."

Two American meteorologist's in 2006 tried to be conclusive. They adjusted for average walking pace, effects of wind, and the fact that runners tend to lean forward (protecting their body fronts from rain but exposing their backs). Then, ignoring physics or mathematics, they used themselves as part of the experiment. Their final conclusion (for now): Over a distance of 100 meters, a person running in heavy rain will stay drier by as much as 40 percent.

For more detailed physics or mathematical arguments, consult The Mathematical Gazette article, Math Forum response, or a rountable of physics responses.

Source: Adapted from New York Times, October 24, 2006