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MHT CET 2026 (14 May, Shift 1) · Moment of Inertia & Radius of Gyration

Moment of Inertia & Radius of Gyration question from MHT CET 2026 (14 May, Shift 1)

Q5MHT CET 2026 · 14 MAY · SHIFT 1Easy

Moment of Inertia & Radius of Gyration

The moment of inertia of a solid sphere about an axis passing through centre of gravity is 2MR25\frac{2MR^2}{5} where M is the mass and R is the radius. The radius of gyration about a parallel axis at a distance 2R2R from first axis is

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Answer: (b)

  1. Parallel axis theorem: I=25MR2+M(2R)2=25MR2+4MR2=225MR2I = \frac{2}{5}MR^2 + M(2R)^2 = \frac{2}{5}MR^2 + 4MR^2 = \frac{22}{5}MR^2
  2. K=IM=225 RK = \sqrt{\frac{I}{M}} = \sqrt{\frac{22}{5}}\,R
  3. So the answer is (b) 225 R\sqrt{\frac{22}{5}}\,R.
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