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COMEDK2024PhysicsRotational Motion

O is the centre of an equilateral triangle A B C . F₁, F₂ and F₃ are three forces acting along the sides A B, B C and A C as shown in figure. What should be the magnitude of F₃ , so that the total torque about O is zero?

Options

  1. A(F₁+F₂ ) 2
  2. B(F₁-F₂ )
  3. C(F₁+F₂ )
  4. D2 (F₁+F₂ )

Correct answer

C. (F₁+F₂ )

Step-by-step solution

For total torque about O to be zero, array rlrl & & F₁ r+F₂ r-F₃ r & =0 & F₃ & =F₁+F₂ array

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