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Center Of Gravity Is An Ambiguous Term

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Posted by Tim on April 16, 2003 04:39:52 UTC

Don

permitt my quote sir:
"Gravitational vectors point toward the 'center of gravity' of the 'gravity generating mass'. The force vector acting on a body under acceleration points in the direction opposite to that of the acceleration vector. Thus the resultant gravitational vectors at all points in a region would converge on the center of gravity of the region. The force vectors at all points in an accelerating region would be parallel and opposite to the acceleration vector."

these force vectors of which you speak are mathematical interpretations of known conditions. they are not real physically measureable phenomenon. if i know the nature of a massive object or objects, shape, size, density, ect. then i can use vectors to calculate the center of mass of that system. it is also allowable to consider a massive object as a point particle from the perspective of it's center of mass when thinking about gravity. there would be know way to measure such "force vectors" as some real physical phenomenon that i know of. please inform me of a device that could do so if you know of one.
in the actual equivalency principle thought experiment the observer is not allowed to know the conditions out side of the elevator hence he is unable to use vectors to calculate the center of gravity of any system outside of the elevator.

regards, tim

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