The radius of gyration of a body about an axis of rotation is defined as the radial distance of a point, from the axis of rotation at which, if the whole mass of anybody is assumed to be concentrated on its moment of inertia about the given axis would be same as with its actual distribution of mass.
Moment of inertia I = mk2
M = mass of the body
K = Radius of Gyration,
SI unit of Radius of gyration is meter.
- If the particles of the body are distributed close to the axis of rotation, the radius of gyration is less.
- If the particles are distributed away from the axis of rotation, the radius of gyration is more