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How does Faraday’s law make electric generators work?
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Magnetic fields and the levels of magnetism of particles, atoms, crystals, and domains.
Faraday’s law of induction is the fundamental principle that enables electric generators to convert mechanical energy into electricity.12
The law states that a change in magnetic flux through a circuit induces an electromotive force (emf) in that circuit. In a generator, this process occurs through the physical motion of a magnetic field relative to a conductor. Specifically:342
- Relative Motion: As the rotor of a generator spins, it creates a time-varying magnetic field that passes through the coils of the stator.5
- Induction: Because the magnetic flux cutting across the stator coils is constantly changing due to this rotation, an emf is induced in the wire.35
- Current Flow: This induced emf drives an electric current through the circuit, effectively generating power.32
The magnitude of the induced voltage is directly proportional to the rate at which the magnetic flux changes over time. By rotating the magnetic field, generators maintain this continuous change, providing a steady supply of electrical energy.352