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MHT CET202619 April 2026Evening ShiftPhysicsRotational MotionActual

A force of 3 i + 2 j - k N acts on a particle with position vector i + j - k m. The magnitude of torque of given force is

Options

  1. A5 , N ,m
  2. B8 , N ,m
  3. C6 , N ,m
  4. D10 , N ,m

Correct answer

C. 6 , N ,m

Step-by-step solution

Given force F = 3 i + 2 j - k N Position vector r = i + j - k m Torque = r F = vmatrix i & j & k 1 & 1 & -1 3 & 2 & -1 vmatrix = i (-1 - (-2)) - j (-1 - (-3)) + k (2 - 3) = i - 2 j - k Magnitude of torque | | = 1^2 + (-2)^2 + (-1)^2 = 1 + 4 + 1 = 6 N m

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