Question

A smooth tube of certain mass is rotated in a gravity-free Space and released. The two balls shown in Fig move towards the ends of the tube. For the whole system, which of the following quantities is not conserved.

A. Angular momentum
B. Linear momentum
C. Kinetic energy
D. Angular speed

Answer 1

Correct Answer - D
As `Sigmatau=0` , Angular momentum, linear momentum remains conserved.
As the two balls will move radially out, I changes. In order to keep to the angular momentum (`L=I omega`) conserved, angular speed `(omega)` should change. Hence.(D)