In reply to Harry Veeder's message of Thu, 11 Aug 2011 11:38:13 -0700 (PDT): Hi, [snip] >> Actually the old argument is correct, in concept, but wrong in magnitude. >> In order to come down in exactly the same spot (assuming a perfectly vertical >> jump), one would have to maintain the same angular velocity (degrees of arc / >> second) in the air that one had on the ground (and, due to the larger radius, >> travel a larger distance at a higher linear velocity parallel to the >> surface). >> Since one's linear velocity is not going to increase (conservation laws), >> one >> always comes down a tiny distance West of where one started. >> Regards, >> > >According to the old the argument if you were jumping at the equator and >stayed in the air for a second in that time the ground would be expected to >move about 1500 hundred feet. If you are wondering why people thought like >this, it is because in aristotelian physics lateral motion could not happen >without an applied force, whereas downward or falling motion was considered >natural or unforced. It was thought a thrown stone would continue to move >laterally because the air would continually rush in behind it and keep pushing >it forward.
...they did have some weird and wonderful notions didn't they. :) But then I suspect people in the future will think the same about us. ;) Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
