Describe the physical and electrical properties of an inductor.

Inductance is the tendency of a conductor to oppose a change in electrical current.

Inductance of a conductor depends on the physical properties of the conductor. Straight wires are typically modeled as having zero inductance.

An inductor, such as a solenoid, is a circuit element that has significant inductance.

The inductance of a solenoid is dependent on the total number of turns, the length of the solenoid, the cross-sectional area of the solenoid, and magnetic permeability of the solenoid’s core. \[L_{sol} = \dfrac{\mu_{core} N^2 A}{l}\]

Inductors store energy in the magnetic field that is generated by current in the inductor. \[U_L = \dfrac{1}{2} L I^2\]

The energy stored in the magnetic field generated by an inductor in which current is flowing can be dissipated through a resistor or or used to charge a capacitor.

The transfer of energy generated in an inductor to other forms of energy obeys conservation laws.

By applying Faraday’s law to an inductor and using the definitiion of inductance, induced emf can be related to inductance and the rate of change of current. \[\mathcal{E} = -L \dfrac{dI}{dt}\]