送交者: steven 于 2005-5-04, 18:21:54:
回答: Don't agree. My impression is that centrifugal force 由 cornbug 于 2005-5-04, 17:58:17:
"Whenever one body exerts force upon a second body, the second body exerts an equal and opposite force upon the first body." If you have a string attaching to an object in a circular motion, the object experienced centripetal force, which keeps the object in its orbit, and the string experienced the centrifugal force. When a satellite orbiting the earth, the earth is also experiencing the gravitational force of the satellte, which is too small to affect the earth, but it still exists.
In other words, earth and its satellites, like the moon, for example, are both orbiting the center of gravity of the whole system. However, since the earth is a whole lot "massier" than its counter parts, the center of gravity lies inside earth, and practically overlaps with the center of gravity of the earth.