NEET2009PhysicsRotational MotionActual
A thin circular ring of mass M and radius R is rotating in a horizontal plane about an axis vertical to its plane with a constant angular velocity . If two objects each mass m be attached gently to the opposite ends of a diameter of the ring, the ring, will then rotate with an angular velocity:
Options
- AM M + m
- B(M-2 m) M+2 m
- CM M +2 ~m
- D(M+2 m) M
Correct answer
C. M M +2 ~m
Step-by-step solution
Apply conservation of angular momentum. aligned L _ i & = L _ f MR ^2 & =( M +2 ~m ) R ^2 ^ ^ & = M M +2 ~m aligned