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 $mg$ 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 ..... .
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 $mg$ 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 ..... .
- [JEE MAIN 2021]
- A
$\frac{2 mgh }{ I +2 mr ^{2}}$
- B
$\frac{2 mgh }{ I + mr ^{2}}$
- C
$2 gh$
- D
$\frac{2 gh }{ I + mr ^{2}}$
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