The angular momentum in a moving coordinate system is given by:
where I is the moment of inertia with respect to a central axis, which is given by:
or, in the continuous case:
Further holds:
Steiner’s theorem is:
if axis C 
axis D.| Object | Moment of Inertia | Object | Moment of Inertia |
|---|---|---|---|
| Cavern cylinder |  | Massive cylinder |  |
| Disc, axis in plane disc through m |  | Halter |  |
| Cavern sphere |  | Massive sphere |  |
Bar, axis  through c.o.m. |  | Bar, axis through end |  |
| Rectangle, axis plane thr. c.o.m. |  | Rectangle, axis b thr. m |  |
Principal axes
Each rigid body has (at least) 3 principal axes which stand
to each other. For a principal axis holds:
The following holds:
with 
Time dependence
For torque of force
holds:
The torque
is defined by: 