The Faraday-Neumann-Lenz law links the circulation of the electric field to the change in magnetic flux. From a practical standpoint, the derivative of the flux acts as a fictitious generator to be inserted into Kirchhoff’s equations. A five-step protocol allows any induction problem to be tackled.

Try it — interactive simulation

Move the magnet in and out of the coil: the changing flux drives an induced EMF, larger the faster the motion.

Simulation Faraday's Law — PhET Interactive Simulations, University of Colorado Boulder, phet.colorado.edu (CC BY 4.0).