Suppose you have *planar* object, that is, one that is flat. An example
of this is a floppy disk, or a cdrom. Suppose the object is
in the x-y plane. If you rotate it the z axis, the moment of inertia is
. If you rotate it by the x or y axes, the moment of inertia is
, or respectively. Then

Wed Jan 22 17:07:34 PST 1997