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Old 09-12-2005, 14:50   #106
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So just to be clear, Your saying the coriollis effect doesn't exist??
I am not sure I understand.
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Old 09-12-2005, 16:41   #107
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Coriolis

Go to www.snopes.com search for coriolis, click on heading.
The coriolis does affect the rotation of wind but not the water in the tub. Do a search for physics and there will be plenty of info.
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Old 09-12-2005, 20:00   #108
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Just a Caveat

I'm leery about the offered origin of posh. There is no real evidence to support this imaginative explanation. Didn't we learn to be wary of clever acronyms with the whole "ship high in transit" myth?

Posh seems to be 19th C. slang for "money," the word deriving through the Romany language. This known linguistic connection seems a much more logical and likely history.
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Old 09-12-2005, 20:25   #109
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I have also heard that the coriolis effect is a myth. aven't tried it myself, but why spoil the fun. After all, we still tell our kids about Santa Claus.
As for POSH, I have seen virtualy no words that have sprouted from acronyms. I tend to believe Capt Jeff's story.
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Old 09-12-2005, 21:09   #110
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coriolis and other tales

Yes Virginia there is a Coriolis Force. It just isn't the only force playing in your toilet bowl. From BC Mike's link:

"Is it possible to detect the Earth’s rotation in a draining sink?

Yes, but it is very difficult. Because the Coriolis force is so small, one must go to extraordinary lengths to detect it. But, it has been done. You cannot use an ordinary sink for it lacks the requisite circular symmetry: its oval shape and off-center drain render any results suspect. Those who have succeeded used a smooth pan of about one meter in diameter with a very small hole in the center. A stopper (which could be removed from below so as to not introduce any spurious motion) blocked the hole while the pan was being filled with water. The water was then allowed to sit undisturbed for perhaps a week to let all of the motion die out which was introduced during filling. Then, the stopper was removed (from below). Because the hole was very small, the pan drained slowly indeed. This was necessary, because it takes hours before the tiny Coriolis force could develop sufficient deviation in the draining water for it to produce a circular flow. With these procedures, it was found that the rotation was always cyclonic."

During one particularly long, boring stretch at sea I made a point to check out the head-spin on both sides of the Equator and it went the same way in both hemispheres - vacuum heads with the outlet hose on the side, so that seems to support the view that the coriolis force is too weak to make a difference most of the time.

As for words that come from acronyms - what about 'okay'?

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Old 09-12-2005, 21:45   #111
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I DID say virtualy. But enlighten me, what is the origin of "okay"?
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Old 09-12-2005, 22:07   #112
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OK

I understand OK derives from a fad in the mid-1800s of using comical abbreviations - OK for 'oll korrect.' This was then picked up by supporters of Martin Van Buren who jumped on its then accepted meaning and attributed it to "Old Kinderhook" - Van Buren's nickname.

Other acronyms that have become words: laser, radar, sonar, scuba.


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Old 10-12-2005, 00:24   #113
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Touche'
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Old 10-12-2005, 08:57   #114
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Okay

Okay is a Yankee invention that came from the newspaper business, in 1839 Boston area I think. It was a notation used when proof reading. It does stand for something, forgotten what.
Possibly O K for all correct, which is not correct but humour was involved.
The correct definition is in the large Websters dictionary that is in the office that I share with the Notary. He is a Yugy so we are in the book often. At times I assist with the correct use of English, but often I give him the tortured English as well.
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Old 10-12-2005, 10:32   #115
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Correct English

Webster's is an American dictionary, so I'd hardly consider it the authority on English - they probably take the u's out of colour and harbour

I admit I prefer CaptJeff's version of "posh" - gypsy word for half, used as slang for halfpenny, then for money in general.

I've heard another version of 'bitter end' - back when the anchor chain was a hemp rope, the end attached to the anchor got dirty, but the ship's end stayed relatively clean - so it was the 'better' end.

One more acronym/word - 'trowal'.

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Old 11-12-2005, 04:58   #116
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The Coriolis Force (Meteorologist’s term for Angular Momentum) certainly exists, but because the Earth's angular velocity is so small (360 degrees per day, or about 7 x 10-5 radians per second), the Coriolis effect isn't really significant over small distances.

The Coriolis effect is not the determining factor in which way your pan, sink, or toilet drains. In a system that is as small, and rotating as slowly, as the water in these, the effect is inappreciable when compared with other factors such as the initial motion of the water, and the shape and orientation of the container. This is especially true in a sink or toilet, where there are jets of water shooting in.
Theoretically, you might detect the Coriolis effect by building a perfectly round, flat basin and making sure the water is initially perfectly still, and the drain is opened very carefully.

The Coriolis Force is calculated thus:
F = -2m x (w x X x v)
Where:
m is the mass of the deflected object (divide the water in the basin into small volumes, and consider each an object)
w is the angular velocity of the rotating object (for Earth, 360 deg./day or about 1E-5 radians/sec)
v is the velocity of the deflected object
X indicates a vector cross-product.

Hence, it takes a:
- large mass
- large angular velocity
- large object velocity
- an object velocity perpendicular to the angular velocity
and
-long distances
for the deflection to take place, contributing to a large and noticeable deflection.

The water in a sink might make a rotation in a few seconds and so have a rotation rate ten thousand times higher than that of the Earth. It should not be surprising, therefore, to learn that the Coriolis force is orders of magnitude smaller than any of the forces involved (ie: gravity). The Coriolis force is so small, that it plays no role in determining the direction of rotation of a draining sink.

Coriolis, Wind, and Weather:

Atmospheric pressure differences (Hi’s & Low’s) tend to push winds in straight paths. Yet, sailors know that winds follow curved paths across the Earth. As air begins flowing from high to low pressure, the Earth rotates under it, making the wind follow a curved path.

In the Northern Hemisphere, the wind turns to the right of its direction of motion (counterclockwise, as seen from above) . In the Southern Hemisphere, it turns to the left (clockwise) around low pressure areas. The Coriolis force is zero at the equator.

On the scale of hurricanes and large mid-latitude storms, the Coriolis force causes the air to rotate around a low pressure center in a cyclonic direction. Indeed, the term cyclonic not only means that the fluid (air or water) rotates in the same direction as the underlying Earth, but also that the rotation of the fluid is due to the rotation of the Earth. Thus, the air flowing around a hurricane spins counter-clockwise in the northern hemisphere, and clockwise in the southern hemisphere (as does the Earth, itself). In both hemispheres, this rotation is deemed cyclonic. If the Earth did not rotate, the air would flow directly in towards the low pressure center, but on a spinning Earth, the Coriolis force causes that air to be deviated with the result that it travels cyclonically around the low pressure center.

The “Global Circulation Wind” rises from the equator and moves north and south in the higher layers of the atmosphere. At around 30̊ latitude, in both hemispheres, the Coriolis force prevents the air from moving much farther. At these latitudes, there is a high pressure area, as the air begins sinking down again. As the wind rises from the equator, there will be a low pressure area close to ground level attracting winds from the North and South. At the Poles, there will be high pressure due to the cooling of the air.

Keeping in mind the bending force of the Coriolis force, we thus have the following general results for the prevailing wind directions:

Worldwide Prevailing (Trade) Wind Directions:
Latitude ~ Direction
90-60̊N ~ NE
60-30̊N ~ SW
30-0̊N ~ NE
0-30̊S ~ SE
30-60̊S ~ NW
60-90̊S ~ SE

HTH,
Gord
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Old 11-12-2005, 14:23   #117
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Quote:
Webster's is an American dictionary, so I'd hardly consider it the authority on English…
I prefer to find this statement humorous, instead of elitist.

Lodesman, I'm sure you meant "authority on British English."

I have high respect for the heights achieved in literature and language by Britain, having studied it at the university; but American English cannot be seen as an inferior version of British English. It has a life and pulse of its own.

An American Dictionary (or "Dictionary of American English") would have the same etymologies, unless overseen by a very nationalistic editor.
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Old 11-12-2005, 14:37   #118
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Websters

I had chosen to let Lodesman's comments slide by. I do agree with you on this. I also thought Websters might be a better authority on a word from Boston, than any English dictionary. All this may be mute because I do not have the dictionary in front of me to varify the brand. Regardless we have all being supplying circumspect evidence to back up our sources anyway. My starboarder answer was most likely all BS. This medium does not always lend itself to precise information, but still much can be learned. I looked up the word okay for the Notary, because I had stated it was the most widely used English language word. The Yugy was the one who new about the newspaper origin.
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Old 11-12-2005, 14:43   #119
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never heard of "British English" before.

There is English - from the country of England

and there is American and Australian versions of English and some other versions from other countries that used to be colonies as well
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Old 11-12-2005, 15:42   #120
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Language is an ever changing thing, as this thread has shown. While American English, may seem slang to the British, British english must sound equally slang when compared to Shakespearean english. Suffice it to say, that without the adaptation of slang into accepted language, we would probably all be trying to communicate in grunts.
I would believe that the term posh came from a Gypsy word, but would have to assume that it started out as a sarcastic term in it's use.
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