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AP EAMCET20228 Jul 2022Morning ShiftPhysicsRotational MotionActual

A body is located at (1,1,1) m and experiences a force of 2 ~N in the direction i + j . The torque acting on the body in N - m is

Options

  1. A(- 2 i + 2 j )
  2. B(- i + j )
  3. C( i - j )
  4. D( 2 i + 2 j )

Correct answer

A. (- 2 i + 2 j )

Step-by-step solution

F =2 1 2 ( i + j )= 2 ( i + j ) We have aligned & j = r F = | array ccc i & j & k 1 & 1 & 1 2 & 2 & 0 array | & = i (0- 2 )+ j ( 2 -0)+ k (0) & =- 2 i + 2 j aligned

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