LuduminaFM-12 · FM-U4 · Planned
Newton’s second law: acceleration investigation
Learning objectives
Use F=ma; design force and mass comparisons; H: explain inertial mass as F/a.
8463 §§4.5.6.2.2 / 8464 §§6.5.4.2.2
DfE single-science pp.35–37 / Combined pp.30–32. Evidence checked 30 September–1 October 2026. Skills: WS2.1–2.7,3.5,3.7; MS3a–3c,4c.
Explanation
Acceleration depends on the resultant force and the total accelerating mass. In a controlled test, vary only force or mass and track the full system. Friction and changing hanging mass can otherwise invalidate a claimed fixed-mass comparison.
Concepts, equations and units: F=ma; N, kg, m/s²; a∝F at fixed mass, a∝1/m at fixed F; inertial mass H.
Prediction, demonstration and game exercise
Predict, observe, explain
Show light gates/trolley/hanging-mass arrangement; include accelerating total mass and friction controls.
Planned learner game exercise
Plan two investigations varying resultant force or total mass; collect repeated accelerations.
Independent practice
Calculate three values, graph a–F and a–1/m, evaluate friction bias.
Original practice example · Shared
A 2 kg trolley system has resultant force 6 N. Find acceleration.
Show working and model answer
Working / reasoning
a = F/m = 6/2.
Answer
3 m/s².
Exit check and success criteria
Two calculations correct plus a controlled plan for both comparisons; H ratio 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 driving force rather than resultant; changing hanging mass without tracking total mass is a fair fixed-mass test.
Practical preparation
RP-P7/RP-C19; AT1,2,3.
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.