I–V characteristics: wire it, record it, plot it sim
Wire a real d.c. bench with plug leads (a rheostat as a potential divider, the ammeter in series, the voltmeter across the part, a protective resistor for the diode and LED), take at least eight readings each way for a resistor, a filament lamp, a diode, an LED and a constantan wire, plot I against V from your own table, and work out R = V ÷ I, plotting R against V for the lamp.
Current of electricity · covers the O-Level, IGCSE, GCSE topic
What the sim shows
A real d.c. bench for the I–V characteristic practical: the rheostat as a potential divider sets the p.d., the ammeter is in series with the component and the voltmeter across it. Every reading comes from the shared circuit model solving the wiring as you made it (meters with their real resistances, the lamp's filament law, the diode's and LED's junctions). Values are illustrative; the lamp's warm-up is slowed so it can be seen.
- The plug you are moving: the part to watch
- Power pack, two digital meters, lead tidy, slide rheostat, protective resistor, component board
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 →
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