Pretty well all our lives we’ve known about the Coriolis Effect. I remember learning in high school that the water in a sink or toilet will spin counter-clockwise in the northern hemisphere and clockwise in the southern hemisphere, due to the earth’s rotation. If you are standing on the equator, you are moving at about 1670 kph, but standing on either pole you are not moving at all. This difference in speed causes hurricanes to rotate as mentioned above.
Being a good student (no comments please) in those days, I took this as fact, and sure enough, every sink or toilet I encountered followed this rule. There is even a Simpson’s episode, where they visit Australia, and the US embassy has a giant machine to make the water in the toilets spin the “proper” way.
So imagine my surprise when I encountered toilets in Central America that had whirling vortexes going in opposite directions. Not only that, they were designed to accelerate the spin by injecting water at an angle to speed up the vortex – in opposite directions!
Another mystery for the great science sleuth to unravel… was it because this close to the equator the spin forces are smaller? They do after all reverse direction less than 10 degrees away, and they must go through zero at that point, and one would think they get weaker as you approach the equator. Costa Rica buys toilets from the lowest bidder. I saw several stamped made in Argentina or made in Chile and a few made in Mexico or even made in USA, so would the designs from the two hemispheres, obviously built to reinforce the natural spin that the designer saw every day, be able to overcome the Coriolis effect in it’s weakened state? How strong was this force anyway?
Off to the world’s biggest library – the Internet – to answer my latest quest for knowledge! (Anything to avoid starting my taxes). And then depression set in. It seems my teachers lied to me! According to pretty much every site I found on the first search, the Coriolis effect is too weak to have any impact on a spinning vortex the size of a drain pipe – even a four inch-er. The spin is purely imparted by the geometry of the sink or toilet, and has nothing to do with the rotation of the earth.
Hmmm… Who to believe now? A quick check around the house shows all my sinks and toilets create counter clockwise vortexes the way God and my high school teachers intended. Could the information on the web be wrong? Could it be contradictory? On the web? Come on…
More searching. More opinions. It does have an impact. It does not. More proofs. Maybe we should do a survey – which direction does the vortex spin in your sink? You have to plug it, fill it, let it stand for a while, then pull the plug. We could publish our own paper!
They say travel forces you to re-examine your basic beliefs about how the world works, but I never thought this would extend to plumbing and basic science learned over 40 years ago!
These things don’t change. Next you’ll be telling me there are more than 103 elements in the periodic table.
No comments:
Post a Comment