inductance

Inductance is a concept within electricity and electronics relating a change in current to a change in voltage. This cause of this effect is a consistent current creating a magnetic field, and then a change in current moving the magnetic field in relation to another conductor, inducing a current. The SI unit for inductance is the henry. Within formulas, inductance is generally represented using the letter L.

Inductance can be created using objects called inductors, which are often coils of wire. While including an inductor in a DC circuit will induce no current unless the current in the circuit is changed, inductors in AC circuits are constantly reacting to the changing direction of the current. Within AC circuits, the current will be temporarily stopped while the magnetic field is changing direction, while the voltage continues to react. This lag is an important factor in the calculation of impedance within an AC circuit. This change in phase angle can be counteracted through the use of capacitors within an AC circuit.

The concept of inductance is very important within a transformer. A transformer works essentially by having two inductors, and having one induce current in the other. The relative number of loops within each inductor determines the voltage and amperage of the output end of the transformer.