The center of gravity is vary intresting to me. According to the dictionary the center of gravity is "An imaginary point representing the weight center of an object; the point about which the object balances in every direction. The center of gravity is that point at which the gravitational potential energy of the body is equal to that of a single particl e of the same mass located at that point and through which the resultant of the gravitational forces on the component particles of the body act."

The center of Gravity is the balincing point of an object. It changes when the object gains a new wieght or if the weight is changed from one side to another. If an object is thrown in the air the center of gravity will always follow a smooth curve. Its and imaginary point of an object in which all of the rest of the object revolves around. If the center of gravity is below the middle of an obejet it will not fall over.

http://www.grc.nasa.gov/WWW/K-12/airplane/cg.html http://www.exploratorium.edu/snacks/center_of_gravity.html