JEE · NEET Previous Year Question
A disc is rotating with angular speed 00. If a child sits on it, what is conserved?
Topic: NEET PYQ
Answer: B. Full step-by-step solution below.
- Alinear momentum
- Bangular momentum
- Ckinetic energy
- Dpotential energy.
Correct answer: B
Solution
(b) : When a child sits on a rotating disc, no external torque is introduced. Hence the angular momentum of the system is conserved. But the moment of inertia of the system will increase and as a result, the angular speed of the disc will decrease to maintain constant angular momentum.angular momentummoment of inertia angular velocity]More Rotational Mechanics PYQs
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