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According to principal of moments, a body will be in rotational equilibrium if-

According to principal of moments, a body will be in rotational equilibrium if- Correct Answer algebraic sum of the moments of all forces acting on the body, about a fixed point is zero

CONCEPT:

  • Principle of moments: A body will be in rotational equilibrium if the algebraic sum of the moments of all forces acting on the body, about a fixed point is zero.
  • Moment of force: It is also called torque.
    • The torque due to a force gives us the turning effect of the force about the fixed points on the axis.
    • It is measured as the product of the magnitude of the force and the perpendicular distance of the line of action of the force from the axis of rotation


EXPLANATION:

  • Rotational equilibrium: According to the principle of moments, a body will be in rotational equilibrium if the algebraic sum of the moments of all forces acting on the body, about a fixed point is zero.
  • Hence option 3) is correct.

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