The law of the machine is(where P = Effort applied to lift the load, m = A constant which is equal to the slope of the line, W = Load lifted, and C = Another constant which represents the machine friction.)

The angle which the normal reaction makes with the resultant reaction is called angle of friction.

If three forces acting at a point be represented in magnitude and direction by the three sides of a triangle, taken in order, the forces shall be in equilibrium.

The forces, which do not meet at one point, but their lines of action lie on the same plane, are known as coplaner non-concurrent forces.

If a number of coplaner forces acting at a point be in equilibrium, the sum of clockwise moments must be __________ the sum of anticlockwise moments, about any point.