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    Re: Equinox, eggs and other questions
    From: Herbert Prinz
    Date: 2002 Mar 17, 18:45 +0000

    Aubrey,
    
    I bet the error was a mixup between sine and cosine !?
    
    A Happy St. Patricks Day to you, too
    
    Herbert
    
    
    Aubrey O'Callaghan wrote:
    
    > However, if my applied mathematics is not completely
    > forgotten the rate of rotation is a fn. of the cos of latitude. At the
    > North pole (true North) then it will rotate at the same rate as the earth,
    > circa. once every 24 hours, at the equator the rotation will be 0. But a
    > little N or S it will rotate very very very slowly cos (< 1deg).
    >
    > Writing this also brings to mind my applied maths class in university in
    > Ireland we had derived the soln. and we found Foucault's pendulum rotated
    > fastest at the equator. As I had spent a little time in Zimbabwe (then
    > Rhodesia) I knew that the Foucault pendulum they had in the University
    > never appeared to significantly rotate... we went thru the calcs. again and
    > found our error !
    >
    > Wishing all a very Green St. Patricks Day !
    >
    > Aubrey.
    >
    > At 13:13 16/03/02, you wrote:
    > >  Rob Gendreau writes-
    > >
    > > >Tradition has it that at the moment of the
    > > >equinox you can stand an egg on end. Not to raise the specter of
    > > >scientific rationalism vs. folklore, but big bets are riding on this in
    > > >my office. Video evidence is being demanded. So an accurate time for the
    > > >equinox is essential.
    > >
    > >=========================
    > >
    > >Such beliefs persist.
    > >
    > >An ex-colleague was in Africa to climb Mount Kilimanjaro, and was in some
    > >sort of tourist-trap placed precisely on the equator. He witnessed a
    > >demonstration, using a bowlful of water with an exit spout at its centre.
    > >At one end of the compound, when the plug was pulled, the water ran out
    > >with a clockwise swirl. Taken to the other end, the swirl was
    > >anticlockwise. My colleague, a physicist of long standing, was gullible
    > >enough to accept that this was the result of the rotation of the Earth, and
    > >being on opposite sides of the equator. Some people will believe
    > >anything...
    > >
    > >If it had been true, however, it could have provided a novel
    > >aid-to-navigation, for anyone wishing to travel East-West along the
    > >equator..
    > >
    > >And if Rob Gendreau's tradition had any validity, then perhaps the
    > >egg-on-end instant could have been used to check a chronometer.
    > >
    > >What a pity that these beliefs fail.
    > >
    > >George Huxtable.
    > >
    > >------------------------------
    > >
    > >george---.u-net.com
    > >George Huxtable, 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
    > >Tel. 01865 820222 or (int.) +44 1865 820222.
    > >------------------------------
    
    
    

       
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