Which direction does water drain at the equator?
Discussion
Just seen this areticle on the BBC:
http://news.bbc.co.uk/1/hi/programmes/fast_track/9...
I don't believe it for a minute! OK, I know that the direction of flow is different in the north/south hemisphere's but
1) Is it really that pronounced either side of the equator, that close?
2) Is that sign even on the equator?
3) Would have thought a round bowl would be better?
4) Don't you need a faster flow than that tiny hole to induce spin?
I think he's some kind of trickster, just flicking the match the direction he wants it to go in!
I did try this on holiday in Kenya once, but can't remember what happened!
http://news.bbc.co.uk/1/hi/programmes/fast_track/9...
I don't believe it for a minute! OK, I know that the direction of flow is different in the north/south hemisphere's but
1) Is it really that pronounced either side of the equator, that close?
2) Is that sign even on the equator?
3) Would have thought a round bowl would be better?
4) Don't you need a faster flow than that tiny hole to induce spin?
I think he's some kind of trickster, just flicking the match the direction he wants it to go in!
I did try this on holiday in Kenya once, but can't remember what happened!
Regiment said:
Isn't the whole theory that water flows different above the equator compared to the below completely rubbish?
It isn't rubbish when applied to whirlpools at sea, with millions of gallons of water, but it is rubbish in terms of your sink/bath etc. That is far more influenced by the way you pull the plug out and other factors. The spinning of the earth has no force over the whirlpool in your bath just like the orbit of the moon doesn't cause a tidal effect in your garden pond.
Interestingly, the 1908 experiment which started the bulls
t rumourmongering observed a counterclockwise rotation in the Northern Hemisphere. The opposite to the BBC piece.

wiki said:
In 1908, the Austrian physicist Ottokar Tumlirz described careful and effective experiments which demonstrated the effect of the rotation of the Earth on the outflow of water through a central aperture.[28] The subject was later popularized in a famous article in the journal Nature, which described an experiment in which all other forces to the system were removed by filling a 6-foot (1.8 m) tank with 300 US gallons (1,100 l) of water and allowing it to settle for 24 hours (to allow any movement due to filling the tank to die away), in a room where the temperature had stabilized. The drain plug was then very slowly removed, and tiny pieces of floating wood were used to observe rotation. During the first 12 to 15 minutes, no rotation was observed. Then, a vortex appeared and consistently began to rotate in a counter-clockwise direction (the experiment was performed in Boston, Massachusetts, in the Northern hemisphere). This was repeated and the results averaged to make sure the effect was real. The report noted that the vortex rotated, "about 30,000 times faster than the effective rotation of the earth in 42° North (the experiment's location)". This shows that the small initial rotation due to the earth is amplified by gravitational draining and conservation of angular momentum to become a rapid vortex and may be observed under carefully controlled laboratory conditions.
Edited by Pothole on Tuesday 16th October 17:42
Nimby said:
Eric Mc said:
Read "Bad Science " by Phil Plait. He has a whole chapter on why this is nonsense.
Do you mean "Bad Astronomy"? Bad Science is by Ben Goldacre (and brilliant, but doesn't mention water draining down plugholes).Ben Goldacre's book is good too (he rightly tears into "Dr" Gillian McKeith).
Doshy said:
hahahahahaha! Classic!!Pothole said:
Doshy said:
hahahahahaha! Classic!!Doshy said:
Pothole said:
Doshy said:
hahahahahaha! Classic!!Pothole said:
Doshy said:
Pothole said:
Doshy said:
hahahahahaha! Classic!!I'll get my coat.
Doshy said:
Pothole said:
Doshy said:
Pothole said:
Doshy said:
hahahahahaha! Classic!!I'll get my coat.
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