Slide 3 of 12
Notes:
The illustration is supposed to represent a rigid body of arbitrary shape with several forces acting on it, all lying in the same plane. Later on, we’ll be more precise about what is meant by “center of gravity.” For a symmetric object, like ellipses, squares, etc., the center of gravity is the same as the geometric center; for an object that isn’t uniform (and isn’t so big that the gravitational field is different at different points in it) the center of gravity is the same as the center of mass.
