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MHT CET 2026 (13 Apr, Shift 1) · Rotational Kinematics & Dynamics

Rotational Kinematics & Dynamics question from MHT CET 2026 (13 Apr, Shift 1)

Q3MHT CET 2026 · 13 APR · SHIFT 1Easy

Rotational Kinematics & Dynamics

A disc of radius 0.4 m and mass 1 kg rotates about an axis passing through its centre and perpendicular to its plane. The angular acceleration is 10 rad/s22. The tangential force applied to the rim of the disc is

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Answer: (b)

  1. Disc: I=12MR2=12×1×0.42=0.08I = \frac{1}{2}MR^2 = \frac{1}{2} \times 1 \times 0.4^2 = 0.08 kg m2^2
  2. τ=Iα=0.08×10=0.8\tau = I\alpha = 0.08 \times 10 = 0.8 N m
  3. F=τR=0.80.4=2F = \frac{\tau}{R} = \frac{0.8}{0.4} = 2 N
  4. So the answer is (b) 2 N.
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