The Shower Curtain Effect
Ever wonder why the shower curtain moves inward when you are in the shower when it should be the other way around? It may seem like a frivolous question but digging around for the answers led Dr. David Schmidt of University of Massachusetts to a 2001 Ig Nobel Prize (doesn’t help the frivolous accusation though). The answers are quite interesting although the causes are inconclusive yet. One of the primary explanations center on Bernoulli Effect Theory:
Bernoulli’s principle states that an increase in velocity results in a decrease in pressure. This theory presumes that the water flowing out of a shower head causes the air through which the water moves to start flowing in the same direction as the water. This movement would be parallel to the plane of the shower curtain. If air is moving across the inside surface of the shower curtain, Bernoulli’s principle says the air pressure there will drop. This would result in a pressure differential between the inside and outside, causing the curtain to move inward. It would be strongest when the gap between the bather and the curtain is smallest – resulting in the curtain trying to wrap you when you get close to it [source: Wikipedia].
Pretty interesting, eh? You get the best questions when you are in the bathroom; probably because that is the only place you are sure what exactly you are doing. I didn’t google the solution for this question while in the bathroom though. But I have solved many a problem in there resisting the temptation to pull a Eureka moment much to the relief of others.


