- 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…