Cambridge IGCSE Physics · Syllabus 0625 · Electricity and Magnetism
Electromagnetic induction
What is Electromagnetic induction?
An e.m.f. is induced in a conductor when the conductor moves across a magnetic field, or when a changing magnetic field links with the conductor; the size of the induced e.m.f. depends on the rate of change and on the number of turns in a coil.
This definition is part of the Electricity and Magnetism chapter in Cambridge IGCSE Physics.
Electromagnetic induction in context
This section is a two-way street with a strict division of labour. Current in a magnetic field produces a force — that is the motor effect. A changing magnetic field produces an e.m.f. — that is electromagnetic induction. Motors use the first; generators and transformers use the second. Keeping those two sentences apart prevents most of the errors in Topic 4.