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The rotational analog of Newton's second law (F = m a) is:
Aτ = I ω
Bτ = I / α
Cτ = I α
Dτ = m α
Answer & Solution
Correct answer: C. τ = I α
1. Net torque τ about a fixed axis equals moment of inertia × angular acceleration.
2. τ = I α, derived from dL/dt with L = Iω for fixed-axis rotation.
3. Iω is angular momentum, not torque.
_Source: NCERT Class 11 Physics Ch 6 §6.9 Theorems on Moment of Inertia + §6.10 Dynamics_
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