Physics · 2018
JEE Main · 15 April 2018, Shift 2 · Q6
A thin uniform bar of length L and mass 8 m lies on a smooth horizontal table. Two point masses m and 2 m are moving in the same horizontal plane…
A thin uniform bar of length L and mass $\displaystyle 8$ m lies on a smooth horizontal table. Two point masses m and $\displaystyle 2$ m are moving in the same horizontal plane from opposite sides of the bar with speeds $\displaystyle 2 v$ and $\displaystyle v$ respectively. The masses stick to the bar after collision at a distance $\displaystyle \frac{\mathrm{L}}{3}$ and $\displaystyle \frac{\mathrm{L}}{6}$ respectively from the centre of the bar. If the bar starts rotating about its center of mass as a result of collision, the angular speed of the bar will be :

Official answer
(2)
$\displaystyle \frac{6 v}{5 \mathrm{~L}}$
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JEE Main 2018 Physics question, with the answer from NTA’s final answer key. Where our answers come from.