Question

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?

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

Answer 1

The correct option is D Angular momentum

$I=\frac{2}{5}m{R}^2{\tau }_{ext}=0\Rightarrow L=constant$