Harry, a few comments in your text below: "Consider a wheel located on Earth's equator (see fig. below). Initially a brake prevents the wheel from turning so the wheel is not turning relative to the ground. Next the brake is released and assuming the axel [axle] of the wheel is frictionless and since the Earth is slowly turning the wheel will begin [continue] to slowly turn about its own centre at the same rate as the Earth's rotation.
For someone standing beside the wheel it might appear as if the brake were still applied. However, if the wheel is turning about its own centre the periphery of the wheel is subject to an associated centrifugal force. The person beside the wheel would deny this unless they knew the brake was released." [no, the centrifugal force is a fictitious force associated to the motion of the non-inertial frame of reference (here the ground-bound frame, or that bound to the bottom of the wheel, which is the same) wrt to an inertial frame of reference (here the Earth center+distant stars frame). This motion, whichever way you look at it, is a simple rotation at 1 turn per day around the Earth axis, at one Earth radius distance] Michel ----- Original Message ----- From: "Harry Veeder" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Thursday, July 26, 2007 9:58 PM Subject: [Vo]:The Earth and the Wheel > > http://web.ncf.ca/eo200/world-wheel.html > > More to come. Comments and questions welcome. > > Harry >
