Electromagnetic induction — FAQ

It's the fundamental principle behind electricity generation in power stations, transformers for changing voltage levels, induction cookers, and many electric motors and generators, powering our modern world.

Faraday's Law tells us the magnitude of the induced EMF, based on the rate of flux change. Lenz's Law provides the direction of the induced EMF or current, stating it always opposes the change in magnetic flux that caused it.

Magnetic flux ($\Phi$) refers to the magnetic field passing through a single loop or area. Magnetic flux linkage ($\lambda$) is the total flux through all turns of a coil, so $\lambda = N\Phi$ for a coil with N turns, where N is the number of turns.