EL-08 · EL-U3 · Planned
Electrical work, power and appliances
Learning objectives
Calculate appliance energy and power; explain p.d. as work per charge and connect chemical/electrical/thermal transfers.
8463 §§4.2.4.1–4.2.4.2 / 8464 §§6.2.4.1–6.2.4.2
DfE single-science pp.39–41 / Combined pp.33–34. Evidence checked 30 September–1 October 2026. Skills: WS1.2,4.5; MS1c,3b,3c.
Explanation
Electrical power gives energy transfer rate. Energy depends on both power and duration; charge-flow energy also depends on p.d. A battery decreases its chemical store while electrical work transfers energy to components and surroundings.
Concepts, equations and units: P=VI=I²R; E=Pt=QV; W, V, A, Ω, J, C, s; optional kWh billing context with conversion.
Prediction, demonstration and game exercise
Predict, observe, explain
Run two rated heaters for specified times; track charge flow and energy separately.
Planned learner game exercise
Select appliances and usage durations for an energy budget; calculate useful/wasted transfers.
Independent practice
Four mixed calculations including time conversion; explain battery versus mains source transfers.
Original practice example · Shared
A 12 V heater draws 2 A for 60 s. Find power and transferred energy.
Show working and model answer
Working / reasoning
P = VI = 12 × 2 = 24 W; E = Pt = 24 × 60.
Answer
24 W and 1440 J.
Exit check and success criteria
Three calculations correct and valid stores/pathways explanation for one appliance.
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
kW and kWh interchangeable; more powerful always more energy regardless of time; electron movement is the energy store.
Practical preparation
Links heater data to RP-P1/RP-C14; optional low-voltage energy measurement AT5,6.
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.