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Rotational Motion question

2020 · Q149
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Rotational Motion question

2020 · Q149

NEETPhysicsRotational MotionMCQ+4 / −1
Find the torque about the origin when a force of 3 j^\hat jj^​ N acts on a particle whose position vector is 2 k^\hat kk^ m.
  1. A
    6 j^\hat jj^​ N m
  2. B
    −-− 6 i^\hat ii^ N m
  3. C
    6 k^\hat kk^ N m
  4. D
    6 i^\hat ii^ N m
View written solutionFree

Correct answer: B

Torque is the moment of Force applied.
τ→=r→×F→\overrightarrow \tau = \overrightarrow r \times \overrightarrow F τ=r×F
τ→=2k^×3j^\overrightarrow \tau = 2\hat k \times 3\hat jτ=2k^×3j^​
τ→=−6i^\overrightarrow \tau = - 6\hat iτ=−6i^ Nm

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