A force or system of forces may cause an object to turn. A moment is the turning effect of a force. Moments act about a point in a clockwise or anticlockwise direction. The point chosen could be any point on the object, but the pivot - also known as the fulcrum - is usually chosen.
The magnitude of a moment can be calculated using the equation:
moment of a force = force × distance
This is when:
A force of 15 N is applied to a door handle, 12 cm from the pivot. Calculate the moment of the force.
First convert centimetres into metres:
12 cm = 12 ÷ 100 = 0.12 m
Then calculate using the values given in the question:
A force of 40 N is applied to a spanner to turn a nut. The perpendicular distance is 30 cm. Calculate the moment of the force.