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Re: Equinox, eggs and other questions
From: Herbert Prinz
Date: 2002 Mar 17, 18:45 +0000
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@huxtable.u-net.com > >George Huxtable, 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK. > >Tel. 01865 820222 or (int.) +44 1865 820222. > >------------------------------