Circular movement around a point or about an axis
which we shall meet with presently as the ellipsoid of gyration at G.
In the case of an axial moment, the square root of the resulting mean square is called the radius of gyration of the system about the axis in question.
Since I~=Ii., I~=o, we deduce 100=3/4Ma2, ~ =4MaZ; hence the value of the squared radius of gyration isfora diameter 3/4ai, and for the axis of symmetry 3/4af.
the square of the radius of gyration with respect to a diameter is ia2.
from its axis (0), if the radius of gyration about a longitudinal axis through G, aiid 0 the inclin - ation of OG to the vertical, FIG.