BRAINCAKEElectromagnetic induction
Revision notes for Electromagnetic induction in Edexcel Physics (1PH0). Every lesson in BrainCake comes with R.E.C.I.P.E. recall steps, a quick check and spaced reviews.
- Inducing a current with a magnet and a conductorWhen a conductor moves relative to a magnetic field, a potential difference is induced across its ends.
- Factors affecting induced potential difference, and the opposing fieldWhen a magnet moves relative to a coil of wire, or a wire cuts through a magnetic field, a potential difference is induced across the conductor.
- Alternators and dynamosAn alternator is a generator that spins a coil in a magnetic field (or spins a magnet inside a coil).
- Microphones, loudspeakers and headphonesSound waves are pressure variations in the air.
- How a transformer induces a current in a second circuitA transformer has two coils of insulated wire wound on the same iron core.
- Transformers and the turns ratio equationA transformer can change the size of an alternating voltage.
- The turns ratio equation for transformersA transformer has a primary coil and a secondary coil wound on an iron core.
- Why the national grid uses high voltagesThe national grid is the network of cables and transformers that carries electrical energy from power stations to homes, schools and factories.
- Step-up and step-down transformers in the national gridTransformers let the national grid use different voltages in different places.
- The power equation for transformersA transformer does not make energy.
- Advantages of high-voltage power transmissionPower stations send electricity over long distances through cables that have resistance.