Electromagnetic induction: magnet, coil and data logger sim
Drag a bar magnet into and out of a coil and watch a centre-zero galvanometer, then say which pole the coil's near end became; run the magnet through the coil on a motor at set speeds, read each peak off a data logger's trace with its cursor, change the speed, the turns and the magnets one at a time, and work out the ratios; drop a magnet through a tube and compare the two peaks; and move a wire up, down and sideways between the poles of a U-shaped magnet.
Electromagnetic induction · covers the O-Level, IGCSE, GCSE topic
What the sim shows
Model: an e.m.f. is induced while the magnetic field linking a coil changes; e.m.f. = − rate of change of flux linkage (Faraday's law, beyond the syllabus). Each magnet is two point poles (0.1 mWb from each pole of the bar magnet, chosen); coils of 100, 200 and 400 turns, 60 mm long; a centre-zero galvanometer of ±200 µA and 500 Ω; a data logger sampling 1000 times a second to 1 mV; a wire with 50 mm in a 0.15 T field and a ±50 µA galvanometer. Idealised: no needle inertia, a steady motor, free fall, no iron core, a uniform field between the jaws.
- The magnet (A, B) or the wire (C): the part you move
- Rail, coils, motor, galvanometers, data logger, tube on a stand, U-shaped magnet
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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