LuduminaFM-02 · FM-U1 · Planned
Mass, weight and gravity
Learning objectives
Calculate weight with supplied g; measure it using a newtonmeter; locate a model centre of mass.
8463 §§4.5.1.3 / 8464 §§6.5.1.3
DfE single-science pp.35–37 / Combined pp.30–32. Evidence checked 30 September–1 October 2026. Skills: WS4.2,4.3; MS3a,3b,3c,4d.
Explanation
Mass measures the amount represented by the inertial/gravitational mass parameter; weight is a force caused by gravity. A fixed object has the same mass in different supplied fields but different weight. A newtonmeter measures force, not kilograms directly.
Concepts, equations and units: W_weight=mg; weight N, mass kg, g N/kg; W_weight distinct from work.
Prediction, demonstration and game exercise
Predict, observe, explain
Compare the same mass on Earth and a different supplied gravitational field; calibrate the balance scale.
Planned learner game exercise
Carry a fixed-mass cargo between model worlds and choose the appropriate measuring instrument.
Independent practice
Three weight problems; graph weight against mass and interpret the gradient.
Original practice example · Shared
A 3 kg object is in a field of 8 N/kg. Find its weight.
Show working and model answer
Working / reasoning
W_weight = mg = 3 × 8.
Answer
24 N.
Exit check and success criteria
Two correct numerical answers and explicit mass/weight distinction.
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
Mass changes when g changes; weight is measured in kilograms.
Practical preparation
Optional newtonmeter measurement, 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.