Physics · 2025
JEE Main · 22 January 2025, Shift 1 · Q29
A uniform circular disc of radius 'R' and mass 'M' is rotating about an axis perpendicular to its plane and passing through its centre. A small…
A uniform circular disc of radius 'R' and mass 'M' is rotating about an axis perpendicular to its plane and passing through its centre. A small circular part of radius $\displaystyle \mathrm{R} / 2$ is removed from the original disc as shown in the figure. Find the moment of inertia of the remaining part of the original disc about the axis as given above.
Official answer
From NTA’s final answer key for this paper.
(3)
$\displaystyle \frac{13}{32} \mathrm{MR}^2$
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.