The principle of moments sim
The moment of a force is the force × the perpendicular distance from the pivot to its line of action.
The principle of moments · covers the GCSE, IGCSE, O-Level topic
What the sim shows
The moment of a force is the force × the perpendicular distance from the pivot to its line of action. The left load turns the rule anticlockwise, the right load clockwise. The rule balances when the anticlockwise moment equals the clockwise moment, the principle of moments: 100 g at 30 cm (1.0 N × 0.30 m = 0.30 N m) balances 200 g at 15 cm (2.0 N × 0.15 m = 0.30 N m). The rule is uniform and pivoted at its middle, so its own weight acts through the pivot and has no moment. Distances are measured from the pivot, not from the end of the rule. Taking g = 10 N/kg.
- Distances from the pivot
- Below: the two moments
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