Electromagnetic induction sim
Moving the magnet changes the magnetic flux through the coil's turns, and a changing flux linkage induces an e.m.f.
Electromagnetic induction · covers the GCSE, IGCSE, O-Level topic
What the sim shows
Moving the magnet changes the magnetic flux through the coil's turns, and a changing flux linkage induces an e.m.f. (Faraday's law): the faster the change, the bigger the e.m.f. So the needle kicks only while the magnet moves; held still, even inside the coil, it reads zero. Pushing in faster, or using more turns, gives a bigger current; pulling out, or turning the magnet round, reverses it. The induced current always opposes the change that causes it (Lenz's law): as the N pole comes in, the coil's near end becomes N and repels it; as it leaves, that end becomes S and attracts it. Work done pushing against this force becomes electrical energy. The coil and galvanometer have 50 Ω of resistance together.
- Red: the magnet's N half
- Below: induced current against time
Use it in your lessons
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