Please can you explain to me what actually is radius of gyration with a figure..?
If the mass of a body is M and the radius of gyration is K, then
I = MK2 ---------- (1)
Also, I = m1r12 + m2r22 + ---------- + mnrn2
I = m (r12 + r22 + r32 + ---------- +rn2) or
But, mn = M
Comparing (1) and (2)
Hence, the radius of gyration of a body about an axis is equal to the root mean square distance of the various particles constituting the body, from the axis of rotation.