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## Moments

The turning effect of a force is called the MOMENT which can be increased by:

1. increasing the size of the force
2. increasing the distance from the pivot to the line of action of the force (using a longer instrument)

Equation:

Moment (Newton metres, Nm)= force (Newtons, N) x perpendicular distance from pivot (Metre, m)

Example: Levers reduce the force needed to perform tasks such as lifting a heavy object.
When a lever is used a force (Effort) is exerted around a Pivot to move an object (Load). Less force is needed to open a door by pushing at the side furthest from the hinge than at the side closest to the hinge as there is greater momentum.

### Balancing moments

If an object is not turning around a pivot, the total clockwise moment is balanced by the total anti-clockwise moment.
The opposing moments are balanced:

sum of the clockwise moments = sum of the anti-clockwise moments

Example using a see-saw:

1. the person on the right exerts a force downward - which causes a clockwise moment
2. the person of the left exerts a force downward - which causes an anti-clockwise moment