DO YOU GET WETTER WHEN WALKING IN THE RAIN THAN YOU DO WHEN RUNNING?

The question of whether people will get wetter if they walk through the rain than if they run through it has been the subject of much bar room discussion . More than that, scien-tists have been considering the problem for many years, and have concluded that many factors can contribute to which method of progress exposes a person to more rain . Some factors are the speed and intensity of the rain, the build of the person, the direction and angle of the rain, and the dis-tance traveled .

The main reason for the debate is the fact that raindrops generally hit both the head and the front of the body . It has been thought that because a runner will be in the rain for a shorter period than a walker will, fewer drops will hit his or her head, and this is a generally agreed-upon hypoth-esis . However, some believe that a runner will be hit with more drops on the front of the body because of his or her increased velocity when running . The balance of these two factors has been put to the test scientifically .

A number of experiments have been performed to deter-mine the best way of keeping dry when moving in the rain, most of which have resulted in a running person ending up less wet than a walking person . While some experiments found that the number of drops per second that a runner re-ceived was the same as for a walker (because the runner was hit more on the front but less on the head), the runner was in the rain for a shorter period and so got hit with fewer drops overall . A number of experiments counting the actual num-ber of drops that hit both a runner and a walker found that the runner received far fewer head drops, but that the front drops for the runner and walker were the same, which again resulted in the runner getting less wet .

In one experiment, the runner ended up getting 40 percent less wet, while in another this figure was reduced to 10 percent. A 1997 experiment found that running in a light rain with no wind resulted in the runner getting 16 percent less wet, while leaning forward and running fast in heavy rain being driven by wind resulted in the runner getting 44 percent less wet . On the basis of these experiments, it’s possible to deter-mine that running is always the best option, particularly in heavy rain .

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DOES WATER TRAVEL DOWN THE DRAIN IN DIFFERENT DIRECTIONS IN THE NORTHERN AND SOUTHERN HEMISPHERES?

Folklore states that water drains down the sink in a counter-clockwise direction in the Northern Hemisphere and a clockwise direction in the Southern Hemisphere, sup-posedly owing to a physical phenomenon called the Coriolis effect. Named after a French engineer, this effect is caused by the Earth’s rotation subjecting a twisting force to fluids flow-ing along its surface . The force occurs over large distances and periods of time, and is reversed in the two hemispheres, which explains why macro events such as hurricanes rotate in opposite directions depending on where they are . When it comes to small bodies of water, such as those contained by a sink or bath, these are far too insignificant to be effected in any noticeable way by Coriolis forces .

The direction in which water drains down sinks and bathtubs depends on the shape and surface of the bowl and drain (most aren’t completely flat), the configuration of the taps and the way in which the water is poured in . Depend-ing on these factors alone, water can drain down in either direction in either hemisphere . If water is swirled into the drain in a clockwise direction, it’s likely to carry on draining in that direction .

The reason for the enduring myth is most likely because it has repeatedly been quoted on television programs and in textbooks .

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