Physics topic 9 : moments

• An alternative name for the turning effect of a force is a moment
• Equation to calculate the moment of a force: Moment of force = Force x Distance (Moment in Nm, Force in N, Distance in m)
• Distance measurement used when calculating a moment: The perpendicular distance from the pivot to the line of action of the force
• If an object is in equilibrium, the clockwise moments are equal to the anticlockwise moments
• Levers make use of moments by increasing the perpendicular distance of the force from the pivot, decreasing the force needed to produce the same moment
• Object with 20N clockwise and 10N anticlockwise moments at 4m and 2m distances respectively will not rotate as the moments are equal, keeping the object in equilibrium
• Levers use a pivot point and the concept of moments to reduce the force needed to lift something; the further away from the pivot point, the less force is required
• Lubricating levers/gears improves efficiency by reducing resistance, resulting in less energy wasted or dissipated as heat to overcome frictional forces