We are familiar with this kind of scene-there is no umbrella when you go out, but the heavy rain is pouring down.Out of instinct, most of us will bend over the humpback and start to rush on the road. I believe that reaching the rainfall place faster will reduce our degree of chicken.But is this instinct really correct?A physicist analyzed it.
Jacques Treiner, theoretical physicist of Paris University, studied the impact of walking speed on rainwater.His opinions may change your strategy.
Treiner first divides the human body into two surface areas-vertical areas such as front chest and back, as well as horizontal areas such as head and shoulders.When static in the rain, only the horizontal surface will be wet from the raindrops falling from the top of the head.
However, once you start moving forward, the situation will change.From your perspective, due to your forward exercise, raindrops seem to fall from a certain angle.This tilting trajectory means that the raindrops that originally fell in front of you will now hit your surface.
The faster you go, the greater the angle and level of the raindrop trajectory, and every step will be hit on your vertical surface.Although this looks suitable for walking slowly, things are not so simple.
Although more raindrops may hit you from the front, the key is that you can reach the rainfall faster, thereby reducing the exposure time in the rain.These two effects offset each other-the higher the speed, the more rain drops per second, but the shorter the overall rain time.
The situation is different for the horizontal surface of the head and shoulders.Treiners calculation shows that no matter how walking, the total number of raindrops falling in these places will not change.You will still be dripped from above at the same speed.
However, if you walk faster and reduce the time exposed to rain, the total amount of water in the final level will decrease.
In short, according to Treiners mathematical model, no matter how your walking speed, the amount of water on the vertical surface is unchanged.However, the amount of water in the head and shoulders decreases as the speed increases.
Of course, there are other factors that play a role. For example, wind may cause rainwater to fall from a certain angle, even if you stand in place, it will be wet.Or, if you are sprinkled with the rain long enough, the rain will eventually drip from the horizontal area to wet your whole body-no matter what your walking speed.But considering that these factors may make the calculation formula too complicated.
Therefore, for the light -free light rain, the physicists conclusion is: "During the rain, it is a good idea to move forward and quickly move forward.Increasing head surface area may offset the benefits brought by the speed.
