Power transmission and the National Grid sim
Drag a plug along a step-up transformer's taps on a model power line and watch the cable current and its I²R loss fall and the town's lamps brighten, work out the loss from your own ammeter readings, then set a real grid's transmission voltage and see the loss fall as 1 ÷ V².
Electromagnetic induction: transformers and high-voltage transmission · covers the O-Level, IGCSE, GCSE topic
What the sim shows
Model. One a.c. loop solved by the circuit solver shared by the circuit figures, with ideal transformers (100 % efficient; Vs ÷ Vp = Ns ÷ Np, Vp Ip = Vs Is). Supply 6.0 V r.m.s., 0.05 Ω inside (chosen). Two cables of 5.0 Ω each (chosen). Lamps 6 V 3 W, their filaments' resistance rising with p.d. Step-up primary 100 turns, secondary taps 100, 200, 400, 800, 1000; the step-down matches. Digital a.c. meters: ammeter reads to 0.001 A, voltmeter to 0.01 V. Real grid panel: 100 MW over 2.0 Ω, chosen typical values. Steady r.m.s. values; the wires' resistance does not change as they warm.
- The step-up's tap plug: drag it to set the cable voltage
- a.c. supply, two transformers, cables on stands, ammeter, the town's lamps, voltmeter
Use it in your lessons
- Try it here: anyone can unlock 2 figures free, and a free account unlocks up to 5. Runs on a laptop, a Chromebook or a phone; nothing to install.
- Present it and share student links with the teacher plan, from US$5 a month, billed yearly.
- Put it on your own website or LMS for US$9, paid once, or every sim from US$29 a month.
Free guide: 12 practicals as sims, and how to run one in a lesson →
Need a version for your exact set-up? Have one made: US$49 a figure in an order of 5.
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