Mechanics · Moments
Chapter 1 · 4
The idea
Moments of forces
The moment (turning effect) of a force as force × perpendicular distance from the pivot, measured clockwise or anticlockwise, in newton-metres — including forces acting at an angle to a rod.
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Mechanics · Moments
Moments of forces
The moment (turning effect) of a force as force × perpendicular distance from the pivot, measured clockwise or anticlockwise, in newton-metres — including forces acting at an angle to a rod.
Why it works
The turning effect of a force
A force doesn't just push a body along — applied away from a pivot, it makes it turn. The size of that turning effect is the moment of the force. It depends on two things: how big the force is, and how far its line of action is from the pivot. A small push far out (like a long spanner) turns more than a big push close in.Force times perpendicular distance
The moment of a force about a point is where is the force and is the perpendicular distance from the pivot to the force's line of action. The unit is the newton-metre (N m). Each moment has a sense — clockwise or anticlockwise — and you must keep track of which, usually by calling one direction positive.Keep reading — free
The rest of the explanation, plus 3 worked examples you step through move by move.
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