Turning Forces

• A heavy weight is called a load and the force that the person applies to the weight is called the effort. The point at which the crowbar turns is called the pivot.

• Moment (Nm) = force (N) x perpendicular distance from the pivot to the line of action of the force (m)

• The centre of mass of an object is the point where its mass may  be thought to be concentrated.

• When a suspended object is in equilibrium, its centre of mass is directly beneath the point of suspension.

• The centre of mass of a symmetrical object is along the axis of symmetry.

A see-saw is an example of the Principle of Moments, this states that for an object in equilibrium:

the sum of all the clockwise moments about any point = the sum of all the anti-clockwise moments about that point.

• The stability of an object is increased by making its base as wide as possible and its centre of mass as low as…