Answer: ω doubles.
- A ω doubles
- B ω halves
- C ω stays the same
- D ω increases to √2 ω
Correct answer: A. ω doubles
Explanation: When a mass falls off, external torque is impulsive for an instant. Immediately after, I = ma² (one mass). By conservation of angular momentum: 2ma² ω = ma² ω' → ω' = 2ω.
Torque about axis O equals the force F multiplied by the perpendicular distance r⊥ from the axis to the line of action of the force, producing rotation.
Concept context
Moment of inertia, torque, angular momentum, rolling motion. Very high JEE weightage.
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