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BITSAT2023PhysicsRotational MotionActual

The torque of a force 5 i +3 j -7 k about the origin is . If the force acts on a particle whose position vector is 2 i +2 j + k , then the value of will be :

Options

  1. A11 i +19 j -4 k
  2. B-11 i +9 j -16 k
  3. C-17 i +19 j -4 k
  4. D17 i +9 j +16 k

Correct answer

C. -17 i +19 j -4 k

Step-by-step solution

Given that torque, =5 i +3 j -7 k Position vector, r =2 i ++2 j + k aligned & = r F = | array ccc i & j & k 2 & 2 & 1 5 & 3 & -7 array | & = i (-14-3)- j (-14-5)+ k (6-10) & =-17 i +19 j -4 k aligned

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