The following is a list of
area moments of inertia. The Area Moment of Inertia or
second moment of area has a
unit of dimension length
4, and should not be confused with the
mass moment of inertia. If the piece is thin, however, the mass moment of inertia equals the area density times the area moment of inertia. Each is with respect to a horizontal axis through the
centroid of the given shape, unless otherwise specified.