LuduminaFM-16 · FM-U6 · Planned
Moments, levers and gears
Learning objectives
Calculate moments and balanced loads; explain levers and gears as transmitting turning effects.
8463 §§4.5.4 / No Trilogy counterpart
DfE single-science pp.35–37 / Combined pp.30–32. Evidence checked 30 September–1 October 2026. Skills: WS1.2,1.4; MS3b,3c,5a.
Explanation
A moment depends on perpendicular distance from the pivot to the force’s line of action. Balanced clockwise and anticlockwise totals give rotational equilibrium. Levers and gears transmit turning effects; they cannot multiply energy.
Concepts, equations and units: M=Fd_perpendicular; N m; clockwise total=anticlockwise total at rotational equilibrium.
Prediction, demonstration and game exercise
Predict, observe, explain
Balance a beam, vary perpendicular distance and compare two gear trains; make clear no energy multiplication.
Planned learner game exercise
Position weights on a crane arm; select a lever/gear arrangement to meet a torque requirement.
Independent practice
Three moment/balance problems and one gears explanation; no advanced torque-speed equation required.
Original practice example · Separate Physics
A 20 N force acts 0.30 m perpendicular from a pivot. Find its moment.
Show working and model answer
Working / reasoning
M = Fd = 20 × 0.30.
Answer
6.0 N m.
Exit check and success criteria
Two correct balances, perpendicular lever arm identified and gear transmission explained.
During practice, compare the prediction with evidence and give an error-specific prompt. The exit item uses a fresh context or fresh values, answered independently.
Misconceptions, practical links and mastery
Check these misconceptions
Use distance along a sloping handle; moment measured in J because dimensions match work; gears create energy.
Practical preparation
Optional moments investigation, AT1,2.
Virtual preparation and revision only. Required hands-on activities and school records remain separate.
Proposed mastery
0: not yet evidenced. 1: supported. 2: independent exit criteria met. 3: successful changed-context transfer. Advance at 2; revisit with fresh retrieval. These are not GCSE grades.