# As shown in the figure, a bob of mass $m$ is tied by a massless string whose other end portion is wound on a fly wheel (disc) of radius $r$ and mass $m$. When released from rest the bob starts falling vertically. When it has covered a distance of $h$, the angular speed of the wheel will be:

Question:

As shown in the figure, a bob of mass $m$ is tied by a massless string whose other end portion is wound on a fly wheel (disc) of radius $r$ and mass $m$. When released from rest the bob starts falling vertically. When it has covered a distance of $h$, the angular speed of the wheel will be: 1. $\frac{1}{r} \sqrt{\frac{4 g h}{3}}$

2. $r \sqrt{\frac{3}{2 g h}}$

3. $\frac{1}{r} \sqrt{\frac{2 g h}{3}}$

4. $r \sqrt{\frac{3}{4 g h}}$

JEE Main Previous Year Single Correct Question of JEE Main from Physics System of Particles and Rotational Motion chapter.

JEE Main Previous Year 7 Jan. 2020

Correct Option: 1

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