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JEE Main202229 Jul 2022Evening ShiftPhysicsRotational MotionActual

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

Using the determinant rule to find the torque τ → = r → × F → = i ^ j ^ k ^ 2 2 1 5 3 - 7 = i ^ - 14 - 3 - j ^ - 14 - 5 + k ^ 6 - 10 Thus, the value of τ → = - 17 i ^ + 19 j ^ - 4 k ^

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