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JEE Main201911 Jan 2019Evening ShiftPhysicsRotational MotionActual

The magnitude of torque on a particle of mass 1 ~kg is 2.5 Nm about the origin. If the force acting on it is 1 ~N , and the distance of the particle from the origin is 5 ~m , the angle between the force and the position vector is (in radians):

Options

  1. A6
  2. B3
  3. C8
  4. D4

Correct answer

A. 6

Step-by-step solution

Torque about the origin = = r F =r F 2.5=1 5 =0.5= 1 2 = 6

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