Question:medium
A disc of moment of inertia \( I \) is rotating with angular velocity \( \omega \). A ring of the same mass and radius, initially at rest, is gently placed coaxially on top of the disc. What is the final angular velocity of the system?
A disc of moment of inertia \( I \) is rotating with angular velocity \( \omega \). A ring of the same mass and radius, initially at rest, is gently placed coaxially on top of the disc. What is the final angular velocity of the system?
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\textbf{Tip:} Use conservation of angular momentum when no external torque acts; always add correct moments of inertia.
Updated On: Nov 26, 2025
- \( \omega \)
\( \frac{\omega}{2} \)
\( \frac{2\omega}{3} \)
- \( \frac{3\omega}{4} \)
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