The moment of a force about a given point is found by multiplying the magnitude of the force by the perpendicular distance from the point to the line of action of the force:
If the distance known is not the perpendicular distance, then trigonometry may be used to find the perpendicular distance and calculate the moment:
Note that the direction, clockwise or anticlockwise, must be specified when talking about a moment. The standard units for moments are newton metres (N m).
Calculate the moment about P of the forces indicated in each of the following diagrams:
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