GCSE Physics Unit 3 Revision

Turning Forces and Centre of Mass

• A moment is the turning effect of a force
• Moment (Nm) = Force (N) x perpendicular distance (m) between line of action and pivot.
• For example, a force on a spanner would be what causes a moment or turning effect on the nut. A larger force would mean a larger moment.
• Using a longer spanner, the same force can exert a larger moment because the distance from the pivot is greater.
• To get the maximum moment (turning effect) you need to push at right angles (perpendicular) to the spanner.
• Pushing at any…