The turning effect of a force is called the of the force.

The of the force both depends on the size of the and how far it is to the pivot or .

moment of force = x

The law of (also called the law of the lever) is stated as follows:
When a body is in equilibrium the of the clockwise moments about any the sum of the moments about the point. There is no moment on a body which is in equilibrium.

The unit for the moment of force is the ().

A is any device which can turn about a . In a working a force called the is used to overcome a force called the .

The conditions for equilibrium are:
(i) The of the in one direction the sum of the forces in the direction.
(ii) The law of must apply.

According the condition for equilibrium, the have to each other.