Coriolis Effect?
The direction of draining water in the tub, sink and toilet is said to be the opposite in Australia. Someone said the Coriolis Effect governs this, and it is a myth. Someone said the CE has nothing to do with it, and it is a myth. Then again someone said it is NOT a myth. I am on the fence with this one, as I cannot argue something I do not have one idea about!! Can you help me? Thanks in
Comments
The Coriolis effect can govern the swirling of fluid flows, and where it does, the swirling is opposite in opposite hemispheres. However, it is only appreciable on a very large scale.
Myth. For small things like sinks and toilets, the Coriolis force is way too weak to overcome assymetries in the geometry of the drain and initial conditions and outside disturbances. Currents and hurricanes are absolutely governed by Coriolis forces. Tornadoes mostly follow the direction of the Coriolis force. Artillery and airplanes have to consider them as slight corrections. But drains do not. I've heard someone claim that if you have a very perfect symmetrical drain in a big tub in carefully controlled conditions at ideal lattitudes, you can get the Coriolis force to effect the flow. But I've never seen it from a reliable source. I know for sure that the shows African kids put on at the equator to extract money from tourists are a scam. Didn't mythbusters bust this? If not, they should.
Edit--that's a pretty good teaching article below. You could probably use it for high school or college "physics for poets" courses. The conservation of angular momentum argument should just be a supplement to what you wrote. I'd put in a paragraph on it. I'd also have left out the part on gravity, which is irrelevant and just confuses the discussion. I don't know where you'd publish something like that, since it isn't anything that any physicists doesn't know, it's just a nice introduction to the topic--some kind of science teacher's magazine?
I wrote a paper on the topic a while back, check it out at http://www.physics.ohio-state.edu/~dvandom/Edu/new...
(Sadly, it didn't get past a reviewer who felt any explanation of the Coriolis force must be based on conservation of angular momentum arguments, so it's "self-published".)