LuduminaFM-10 · FM-U3 · Planned
Free fall and terminal velocity
Learning objectives
Explain free fall and terminal speed; P: draw and interpret changing-force/velocity traces.
8463 §§4.5.6.1.5 / 8464 §§6.5.4.1.5
DfE single-science pp.35–37 / Combined pp.30–32. Evidence checked 30 September–1 October 2026. Skills: WS1.2,3.3,3.5; MS4a.
Explanation
Freely falling near Earth means gravity is the only force considered in the ideal model. With drag, increasing speed increases resistance until it balances weight. At terminal speed, acceleration is zero but the object is still moving.
Concepts, equations and units: Near-Earth free-fall a≈9.8 m/s²; weight/drag N; terminal velocity when resultant=0.
Prediction, demonstration and game exercise
Predict, observe, explain
Drop an ideal body then a model parachute; label forces as speed changes.
Planned learner game exercise
Alter parachute area and payload, predict initial acceleration and terminal speed, compare model traces.
Independent practice
Explain the stages; P: sketch and annotate v–t for parachute opening.
Original practice example · Shared
A falling object has weight 20 N and upward drag 20 N. State its resultant and acceleration.
Show working and model answer
Working / reasoning
Opposite equal forces cancel; F_resultant = 0, so F = ma gives a = 0.
Answer
0 N and 0 m/s²; it may continue at terminal velocity.
Exit check and success criteria
Correct force balance at terminal speed and distinction between free fall and falling with drag; P trace consistent.
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
Terminal velocity means stopped; all falling objects have constant acceleration; shared content includes every separate-P graph requirement.
Practical preparation
Optional parachute investigation, AT1,2,3; not an RP.
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.