This definitions covers Key Definitions within Electromagnetic Induction for GCSE Physics. Revise Electromagnetic Induction in Magnetism for GCSE Physics with 18 exam-style questions and 12 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 7 of 14 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
📖 Key Definitions
- Electromagnetic induction
- The process by which a changing magnetic field induces a potential difference in a conductor. A current flows if the circuit is complete.
- Induced EMF (electromotive force)
- The potential difference (voltage) generated in a conductor due to a changing magnetic flux. Measured in volts (V).
- Magnetic flux
- A measure of the number of magnetic field lines passing through a given area. Changes in magnetic flux cause induction.
- Lenz's law
- The induced current always flows in a direction that opposes the change that caused it (conservation of energy principle).
- AC generator (alternator)
- A device that converts mechanical energy into alternating electrical energy using electromagnetic induction. Uses slip rings to connect the rotating coil.
- Slip rings and brushes
- Components in a generator that allow the rotating coil to maintain electrical contact with the external circuit without wires becoming tangled. They produce AC output.