JEE Main2002PhysicsRotational MotionActual
Initial angular velocity of a circular disc of mass M is ₁ . Then two small spheres of mass m are attached gently to diametrically opposite points on the edge of the disc. What is the final angular velocity of the disc?
Options
- A( M+m M ) ₁
- B( M + m m ) ₁
- C( M M +4 ~m ) ₁
- D( M M+2 m ) ₁
Correct answer
C. ( M M +4 ~m ) ₁
Step-by-step solution
Angular momentum = conserved 1 2 MR ^2 ₁=2 m R^2 + 1 2 MR ^2 = M ₁ M +4 ~m