Question

What is self-inductance? Name the factors on which self-inductance depends.

Answer 1

Self-induction is the process by which an electromotive force is induced in a circuit by a varying current in that circuit. Basically, an inductor works based on the principle of self-inductance. Self-induction is a physical effect and the primary components where it is used are the inductor and to some extent the transformer.

Complete step-by-step answer:
Self-inductance can be defined as an inductance in which an electromotive force is produced by self-induction. It can also be defined as the property of the coil due to which it opposes the change of current flowing through the circuit.
This property of the coil only opposes the changing current (alternating current) and does not affect the steady current that is (direct current) when flows through it. The unit of inductance is Henry (H).

Self-inductance depends on-
1. Size of coil.
2. Shape of the coil.
3. Material of the coil.
4. Medium.
Self-inductance in a solenoid can be given as $\dfrac{\mu {{N}^{2}}I}{A}$.

Additional Information: The following points are often drawn about Self Inductance.
The value of the inductance will be high if the magnetic flux is stronger for the given value of current. The value of the Inductance also depends upon the material of the core and the number of turns in the coil or solenoid. The higher are going to be the worth of the inductance in Henry, the speed of change of current is going to be lower.
1 Henry is also equal to 1 Weber/ampere.
The solenoid has large self-inductance.

Note: Inductors by themselves are not all that useful unless combined with resistances or capacitances. For example, combining an inductor with a capacitor can create a resonant circuit used in analog filters or oscillators. Inductors can be used to compensate transmission line capacitances.
Similarly, a transformer uses self-inductance mostly when it is not loaded on the load side; in this case the self-inductance limits the current through the transformer’s primary windings. When the transformer is properly loaded then the self-inductance becomes less relevant.