Physics · 2020
JEE Main · 7 January 2020, Shift 1 · Q2
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.…
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 $\displaystyle r$ and mass $\displaystyle m$. 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 :Official answer
(1)
$\displaystyle \frac{1}{r} \sqrt{\frac{4 g h}{3}}$
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JEE Main 2020 Physics question, with the answer from NTA’s final answer key. Where our answers come from.