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AP EAMCET202125 Aug 2021Morning ShiftPhysicsRotational MotionActual

The torque due to force F =3 i -2 j - k acting at a point r =8 i +2 j +3 k is

Options

  1. A-4 i -17 j +22 k
  2. B4 i +17 j -22 k
  3. C8 i -17 j +22 k
  4. D-4 i -17 j -22 k

Correct answer

B. 4 i +17 j -22 k

Step-by-step solution

Given, aligned F & =3 i -2 j - k , r =8 i +2 j +3 k & = v F =(8 i +2 j +3 k ) (3 i -2 j - k ) & = | array ccc i & j & k 8 & 2 & 3 3 & -2 & -1 array | & = i (-2+6)- j (-8-9)+ k (-16-6) & =4 i +17 j -22 k aligned

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