A circular disc of radius b has a hole of radius a at its centre (see figure). If the mass per unit area of the disc varies as  , then the radius of gyration of the disc about its axis passing through the centre is :

Mass per unit area of a circular disc of radius a depends on the distance r from its centre as σ(r) = A + BrThe moment of inertia of the disc about the the axis, perpendicular to the plane and passing through its centre is :

A black disc spins with angular speed   and a point on the edge moves at speed  . A pink disc spins with angular speed  , with a point on the edge moving at speed  .Which disc has a larger radius?

The radius of gyration (Rg) is directly proportional to the molecular weight Ma, where ‘a’ is a constant. The value of ‘a’ for a spherical molecule is

The radius of gyration of a sphere of radius R about a tangent is :-

A uniform disc of radius 20 cm and mass 2 kg can rotate about a fixed axis through the centre and perpendicular to its plane. A massless cord is round along the rim of the disc. If a uniform force of2 newtons is applied on the cord, tangential acceleration of a point on the rim of the disc will be :-