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A thin uniform bar of length L and mass 8 ~m lies on a smooth horizontal table. Two point masses m and 2 ~m moving in the same horizontal plane from…

JEE Main 2018 — Physics Mechanics

2018mcqhard

A thin uniform bar of length L\mathrm{L}L and mass 8 m8 \mathrm{~m}8 m lies on a smooth horizontal table. Two point masses m\mathrm{m}m and 2 m2 \mathrm{~m}2 m moving in the same horizontal plane from opposite sides of the bar with speeds 2v2 \mathrm{v}2v and vvv respectively. The masses stick to the bar after collision at a distance L3\frac{\mathrm{L}}{3}3L​ and L6\frac{\mathrm{L}}{6}6L​ 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: JEE Main 2018 Physics, Rotational Motion — question figure

Official previous-year question

Held on 15 Apr 2018 · Verified 6 Jul 2026.

Options

  1. A

    v6 L\frac{\mathrm{v}}{6 \mathrm{~L}}6 Lv​

  2. B

    6v5 L\frac{6 \mathrm{v}}{5 \mathrm{~L}}5 L6v​

  3. C

    3v5 L\frac{3 \mathrm{v}}{5 \mathrm{~L}}5 L3v​

  4. D

    v5 L\frac{\mathrm{v}}{5 \mathrm{~L}}5 Lv​

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