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General Discussion & Feedback => Radio Show & Podcast Feedback => Topic started by: mcgoogus on 25/10/2005 00:42:05

Title: Coriolis Force - Myth?
Post by: mcgoogus on 25/10/2005 00:42:05
On a recent episode a call-in asked about the direction water spins when it goes down a drain.  The answer given, though I'm not sure because it was never named, referred to the Coriolis Effect.  Now I was led to believe that the drains being affected by the Coriolis Force was a myth.  

http://en.wikipedia.org/wiki/Coriolis_effect#Draining_bathtubs.2Ftoilets

So my question:  Is it fact or fiction?
Title: Re: Coriolis Force - Myth?
Post by: daveshorts on 25/10/2005 19:32:21
You are entirely right, although the coreolis force does act in opposite directions on either side of the equator it is much too weak to have an effect on something as small as a basin of water. It does however affect how low pressure systems rotate either side of the equator....
Title: Re: Coriolis Force - Myth?
Post by: chris on 26/10/2005 08:38:55
You're right. The Coriolis 'effect' is an apparent force acting perpendicular to the direction of travel and caused by the rotation of a body - i.e. the earth.

This applies in the context of weather systems where it contributes to the anticlockwise rotation of storms, like hurrican Wilma, in the northern hemisphere.

I buggered up and suggested that it might affect water in toilet bowls and sinks too. The explanation of the origin of the Coriolis effect was correct, but the application was wrong.

Apologies.

Chris

"I never forget a face, but in your case I'll make an exception"
 - Groucho Marx