Mysteries

# The Shower-Curtain Effect Is What Causes Those Random Curtain Clings While You Bathe

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Bathrooms are windless, that's probably safe to assume. Regardless, you've likely experienced the cling of a shower curtain that randomly flew at you while you're just trying to lather up your scalp. How does this happen? Why?! We're pretty sure the answer is not ghosts, but the scientific explanation has puzzled physicists for years.

Related: Common Mistakes People Make In The Shower

## Hope You're Ready For A Hug

There are a few theories floating around to explain why this happens. What do you think?

1. The hot air from the shower rises, so colder air from outside the shower rushes in to fill the void. As it rushes in, it swoops up the curtain and sticks it right on your damp leg. Interesting theory, but someone actually took an ice cold shower to test it out. Result: The curtain still clinged. Next!
2. Bernoulli's principle is a popular guess. This theory basically states that the movement of the water causes movement of the air in the shower. The moving air lowers the air pressure on the inside of the curtain, which allows the higher-pressure air outside the curtain to waft it inward.
3. If you've ever held a spoon near running water and seen the water bend, that's the Coanda effect. If you held the spoon up while letting it move freely, you'll see that the water gravitates toward the water. This may be the case with the shower curtain being pulled to the stream of the shower.
4. It may happen due to a vortex, according to David Schmidt, who won an Ig Nobel Prize for his work on the effect. According to Gizmodo, "When he did a computer model of how the spray from a shower head moves air inside a shower cubicle, he showed that a vortex develops. The vortex is horizontal, meaning it would look like a sort of jar rolling on its side, drawing the shower curtain along with its motion as it rolls.

Related: You Can Be Allergic To Water

## We Need Answers And We Need Them Now

One reason this phenomenon is still largely a mystery is because, quite frankly, scientists have bigger fish to fry. Studying a weird, maybe only slightly annoying thing that happens when you're performing a menial task isn't a huge priority for physicists. Can you blame them? For now, it's a fun shower thought that you can literally observe in the shower at the same time.

Is there something you're curious about? Send us a note or email us at editors (at) curiosity.com. And follow Curiosity on Facebook, Instagram and Twitter.

## Watch And Learn: Fascinating Content About The Shower

#### The Shower Curtain Mystery

##### STEMbite: Shower Curtain Mystery
STEMbite – STEMbite

### Key Facts In This Video

1. Shower curtains commonly creep inwards when the shower is on. 00:10

2. One theory about the creeping shower curtain involves Bernoulli's principle, and states that lower air pressure inside the shower would cause the curtain to move into the tub. 00:58

3. Scientists still haven't developed an airtight explanation for why the shower curtain creeps up on you. 01:25

#### Why You Should Pee In The Shower

##### Why You Should Pee In The Shower
SourceFed – SourceFed

### Key Facts In This Video

1. If everyone in New York City flushed one fewer time, the city would save approximately 36.8 billion liters of water in one year. 01:00