Moment

Turning effect of force ⇒ moment Lever ⇒ rigid bar resting on pivot or fulcrum → used to move a load when a force is applied

When force is applied ⇒ load experiences a turning force. Rigid bar ⇒ is hinged at the pivot ⇒ can make a sweeping movement only.

Turning effect of a force is proportional to:

  • Perpendicular distance form the pivot where the force is applied
  • magnitude of force applied

Turning effect of a force ⇒ also known as torque


Definition

Moment of a force, M or torque, about a pivot is the product of the force F and the perpendicular distance d from the pivot to the line of action of the force #PhysicsDefinitions

where F = force applied (N) d = perpendicular distance from the pivot to the line of action of the force (m)

SI unit N m ⇒ it is a vector quantity. Moment of force has direction a clockwise rotation about pivot ⇒ is a clockwise moment. Anticlockwise rotation about pivot ⇒ is anticlockwise moment

Important ⇒ in order to create moment ⇒ line of action of force must not pass through pivot


Principle of Moments


Center of Gravity


Stability (Pure Only)