flushing toilets swirl different in each hemisphere?
 

I've always held this as a widely regarded truth...after all, there is a Simpsons episode about it! But I have a page-a-day calendar called "Fact or Crap?" and the question today pertained to this. I almost didn't look for the answer, knowing what it would be, but it turned out to be Crap! This is what it said:

"There is somethign called the Coriolis force, which, in short, is what happens when air flows from high to low pressure under the earth's rotation. This deflects wind to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. The effect is noticeable, however, only for large-scale motions, such as weather conditions."

I can't say im fully convinced...has anyone here studied this formally and have the answer?

When I was in Indonesia last December I noticed that the water went down the drain the opposite way to how it does when I am in the northern hemisphere...

In searching for your answer, I found this instead: The Straight Dope: Urinal 101: Aim for the back wall or the water?. I'm easily distracted.

Anyway, (and I have no links to back this up), from what I recall, the Coriolis Force is very very slight. The flush direction of a toilet will be much more affected by the shape of the toilet and the direction of the water jets.

EDIT: Ah, here we go, will you accept the word of Snopes? They say 'false'.

It ranks right up there with Aussies having have their blood spun in the opposite direction to collect platlettes. Simply not true....of course you could engineer a toilet to drop water in an opposite direction just to perpetuate the myth...:D

Just ask the Aussies on this board which way the water spins when it goes down the sink! The toilet is not the best way to check this as Redlemon said ... :thumbsup:

That Straight Dope site is great!

Well the sink in my bathroom drains counter-clockwise when I pull the plug, and I'm in Australia :)

I love the straight dope, best site ever. Cecil knows his stuffl

This is correct. In a theoretical world where nothing else but Coriolis occurs, the water would go the other way. It's practically non-existent in the scope of a flushing toilet.

To be frank, I haven't found that there is any discernible 'swirling' of any kind when the toilet flushes.

It depends on the toilet, really. Some have jets that force the water to swirl in one way or the other. In my toilet (I can't believe I just went up to flush it for this) water spins counter-clockwise, but that's mostly because there's 1 jet of water on the right side pointing down and to the wall, 1 on the left side pointing down and to where I'm standing. So there's no Coriolis effect deciding on it; the toilet manufacturers did it. However, what if there weren't those jets? As it said above, the Coriolis effect is just plain too small to do anything. It has a huge effect on the weather as this link shows (Scroll down to "what causes the wind to blow", about halfway down). It changes the winds a lot. But, the toilets? If the manufacturer put those little jets, that will determine. Otherwise, it's random, really; there's so many variables that determine it. Probably, given 1 million toilets without jets in the northen hemisphere, 500,010 will go one way and 499,990 will go the other. There is an effect, it's there, but it's really freaking small and in no way is it a law.

...I need a hobby.

You do realize that Cecil is not a real person right? He's just an imaginary character created by the writers of the straight dope.

Well at least the shit still goes down the drain.

A teacher of mine went to the equator on holiday. There were people there who would take your money, stand on one side of the imaginary line and drop water down a hole in a bucket that would spriral one way, and then the other way, and then straight down when they were on the line. Truth is they just wobbled the bucket slightly to create the illusion.

I always wondered about the toilet thing :p

I don't know if any of you have heard of Arj Barker, but he's a comedian and he has a really funny bit on the toilet water's swirl in Australia. I'd probably ruin it if I tried to recreate it in text form, as a lot of the joke is in the way he says it and some actions you just have to see him make on stage. But, basically he says that it's true, and that in the US toilets flush down clockwise, and in Australia it's the opposite, and toilets flush counter-clockwise and up creating a "giant brown twister." I know it's childish, but I found it hilarious...especially when he referred to it as a "crap tornado."

Well since the toilets are out of the question, everyone should fill up their sink and let it drain out. Like I said, in Australia mine drains counter-clockwise, without any jets or help at all.

I don't think the sink would be a good test either. Some factors that would affect the way it drains, off the top of my head, would be: whether the sink itself is perfectly level, whether the drain opening is perfectly round, gunk on the sides of the drain pipe, and the way the pipe is routed.

Arj Barker's routine about surfing at the 2002 Melbourne Comedy Festival was freaking hilarious.

Yes, but our toilets work different to ones I've seen in the US - which tend to have a lot more water in the bowl
For the unitiated - Aussie toliets have very little water in the bottom, and the flushing is actually water being put into the bowl when you press the magic button - its kinda hard to see how the water empties because it is quite a flood.

In the US, there is quite a lot of water in the bowl, which is emptied and then refilled, thus you would be able to notice the how the water empties.

Thats why I brought this up in the first place. I remember when I was on a ship, which we went down to Australia, the water created a clockwise vortex in the Northern Hemisphere, and a counterclockwise vortex in the Southern Hemisphere. And when we were near the equator there was no discernable direction when the water went down the sink.

The water here in California goes down the drain clockwise. It doesn't mater what type of sink you have, or bathtub for that matter. With no other forces (i.e. jets from the toilet) the water in the Northern Hemisphere will make a Clockwise Vortex. I even saw this cool documentary on Lake Peigneur, in Louisianna, where they accidently drilled a hole in the top of a salt mine (while drilling in the lake for oil). The whole lake went down this 14" hole into the salt mine, sucking in barges and everything. The vortex that sucked down these barges was going clockwise! Get the DVD here or catch it on the history channel.

to make this short now, just fill up your sinks, pull the plug and watch the vortex. Those in the North will see it go clockwise, those 'down under' will see it go counterclockwise. :thumbsup: