David, at German universities this an typical question for physics students in their written exam after their first year of study. If an body if moved by an force F along the differential distance ds then the work dw = F * ds is necessary to do that and is stored as kinetic or potential energy of the body where both F and ds are vectors and "*" denotes the scalar product of them. In the case of an circular motion F and ds are orthogonal to each other and the scalar product is 0 along the whole line of motion. Result: No work is used or necessary to keep the satellite on its orbit and so no additional energy ist stored in the satellite. Pretty much the same applies to your charged particle example.
Regards Ulrich Bangert > -----Ursprüngliche Nachricht----- > Von: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] Im Auftrag von David Dameron > Gesendet: Mittwoch, 30. Mai 2007 08:12 > An: [email protected] > Betreff: Re: [time-nuts] Pendulums & Atomic Clocks & Garvity > > > Hi Didier and all, > This is because the gravitational force is perpendicular to > the velocity (at least for a circular orbit), so the result > is a change only in the direction of the velocity, not the > magnitude. For an elliptical orbit, the satellite speeds up > and slows down when the gravity force has a non-perpendicular > component. > > This is the same thing that happens with the (v x B) magnetic > force on a moving charged particle. -Dave D. > > >Now, there is something else I would be missing under your scenario. > When an object is subjected to acceleration, it gains speed. > The product > of force by speed is stored in the object in the form of > kinetic energy. > If the satellite is constantly being subjected to unbalanced > forces and > falls, it should be accelerating and accumulating energy, yet it does > not. 10 years later, a satellite has no more kinetic energy > than when it > was launched (if all goes well...) Actually, satellites that are in > elliptical orbits trade kinetic energy for potential energy, > just like > the old L-C network constantly trades electrostatic energy > for magnetic > energy. But the sum remains constant, except for friction on > imperfect > vacuum of space. > > So what is it that prevents the satellite that is constantly > subjected > to unbalanced forces to not gain speed and energy? > > > > > > > _______________________________________________ > time-nuts mailing list > [email protected] > https://www.febo.com/cgi-> bin/mailman/listinfo/time-nuts > _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
