A solid sphere is rotating freely about its symmetry axis in free space . The radius of the sphere is increased keeping its mass same . Which of the following physical quantities would remain constant for the sphere ?

Options

A. Angular velocity
B. Moment of inertia
C. Rotational kinetic energy
D. Angular momentum

Answer

D

Explanation

As there is no external torque acting on a sphere , i.e., `tau_("ex") = 0`
So, `(dL)/(dt) = tau_("ex") = 0` i.e., L = constant
So angular momentum remains constant .