On Inductance

Ampere's equation states that the magnetic field wraps around the current in a steady state. This means that electrons might leave a conductor and spin back onto that same conductor around the atoms and molecules in the surrounding media. The normal of the electron spin is represented by magnetic field lines.

Faraday's law will be the focus of this post. Faraday's law states that a changing magnetic field will induce an electric field according to the left hand rule. This is opposite the right hand rule used in Ampere's law. We must explore why this is.

A magnetic field is a tight curl of electrons spinning in the same direction. Electrons that were spinning in the opposite direction because of the movement of the magnetic field or the circuit within the magnetic field will push outwards and cause a momentary electromotive force through a circuit. Electric motors take advantage of this.

In the figure below the circulating electrons counter-clockwise are due to an external magnetic field. Really the electrons are just lining up due to collisions. In between the spinning due to magnetism exists a counter-spin. In this case clockwise. This clockwise spin is not constrained to a small tight spin so it pushes outwards to a larger and larger Faraday current until it can produce an electromotive force in a circuit.

This is how a changing magnetic field induces an electromotive force in a circuit.