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
