Physics · 2021
JEE Main · 26 February 2021, Shift 2 · Q8
A cord is wound round the circumference of wheel of radius r. The axis of the wheel is horizontal and the moment of inertia about it is I. A weight…
A cord is wound round the circumference of wheel of radius $\displaystyle r$. The axis of the wheel is horizontal and the moment of inertia about it is I. A weight mg is attached to the cord at the end. The weight falls from rest. After falling through a distance ' h ', the square of angular velocity of wheel will be :
Official answer
(3)
$\displaystyle \frac{2 \mathrm{mgh}}{\mathrm{I}+\mathrm{mr}^2}$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.