NEET2010PhysicsCenter of Mass, Momentum and CollisionActual
A thin circular ring of mass M and radius r is rotating about its axis with constant angular velocity . Two objects each of mass m are attached gently to the opposite ends of a diameter of the ring. The ring now rotates with angular velocity given by
Options
- A(M+2 m) 2 m
- B2 M M +2 ~m
- C(M+2 m) M
- DM M+2 m
Correct answer
D. M M+2 m
Step-by-step solution
In the absence of external torque, angular momentum remain constant aligned L & = I = I ^ ^ MR ^2 & =( M +2 ~m ) R ^2 ^ ^ & = M ( M +2 ~m ) aligned