The induction of an e.m.f in a conductor in a changing magnetic field, which induces a current through the conductor

Placing a wire (or another conductor) in a magnetic field, Moving a bar magnet in a coil of wire - a current is also induced if the coil forms a complete circuit

There will be a flicker in the ammeter

As the magnet approaches the coil, there is a change in flux through the coil, inducing an e.m.f and a current in the coil, Due to Lenz's law, the current opposes the motion of the magnet, slowing it down, No e.m.f is induced as the magnet goes through the coil's centre, but as it leaves the coil again, there is a change in flux

The induced e.m.f in a circuit, caused by a change in magnetic flux, is proportional to the rate of change of flux linkage

The induced e.m.f in a conductor will induce a current, that opposes the original change in the magnetic field (flux) - a magnetic field is also induced around the conductor

Induced e.m.f, ϵ (Volts, V) = -(Number of Coils, N × Change in Flux Linkage, Δϕ (Webers, Wb) / Change in Time, Δt (s)

Due to Lenz's law

We know that Faraday's Law states that the induced e.m.f is proportional to the rate of change of flux linkage, We know that the flux linkage = BANcosθ, where θ for this experiment = ωt, ω = 2πf, where f is the frequency of rotation of the coil, Increasing the frequency of rotation also increases the amplitude of the induced e.m.f

An AC is produced when the current changes direction, As the coil is spinning, the direction of the induced e.m.f is constantly changing, inducing an AC as the direction of the current is also changing

A coil is initially rotated through an external power source, or a magnetic field can be made to rotate around a coil, This changes the magnetic flux through a coil, inducing an e.m.f in the coil, This e.m.f induces a current, which produces its own magnetic field, This field interacts with the external magnetic field, producing a force on the coil that causes it to rotate, This rotation causes another change in magnetic flux through the coil, allowing the process to repeat

Magnetic Flux Density, B (Tesla) ÷ Area, A (metres², m²) × Number of Coils, N × Angular Velocity, ω (rad/s) × sin(Angular Velocity × Time)

The induction of an e.m.f in a secondary coil of wire, caused by changing the current in the primary coil with leads to a change in the magnetic field around it

The second coil must be in the changing magnetic field of the first coil

Transformers