COMEDK · Physics · 8. Rotational Motion
A disc of moment of inertia \(4 \mathrm{~kg}-\mathrm{m}^2\) revolving with \(16 \mathrm{rad} / \mathrm{s}\) is placed on another disc of moment of inertia \(8 \mathrm{Kg}-\mathrm{m}^2\) revolving \(4 \mathrm{rad} / \mathrm{s}\). The angular frequency of composite disc
- A \(4 \mathrm{rad} / \mathrm{s}\)
- B \(\dfrac{3}{16} \mathrm{rad} / \mathrm{s}\)
- C \(8 \mathrm{rad} / \mathrm{s}\)
- D \(\dfrac{16}{3} \mathrm{rad} / \mathrm{s}\)
Answer & Solution
Correct Answer
(C) \(8 \mathrm{rad} / \mathrm{s}\)
Step-by-step Solution
Detailed explanation
The principle of conservation of angular momentum states that the total angular momentum of the system remains constant when no external torque acts on it. Let \(I_1 = 4 \text{ kg-m}^2\) and \(\omega_1 = 16 \text{ rad/s}\) be the moment of inertia and angular velocity of the…
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