Question

What causes the inductance?

Answer 1

1. Inductance is the nature of an electrical conductor which opposes a change in the electric current flowing through it.
2. The two types of inductance are:
   2.1 Self-inductance: An electromotive force is induced due to a change in the current or magnetic flux of the coil. This phenomenon is termed self-inductance.
   The mathematical expression for self-inductance:
   $\mathrm{L}=\frac{\mathrm{N\varphi }}{\mathrm{I}}$
   where,$\mathrm{L}$ is the self-inductance, $\mathrm{N}$ is the number of turns, $\mathrm{\varphi }$ is the magnetic flux, and $\mathrm{I}$ is the current
   2.2 Mutual inductance:
   
   The change in the current or magnetic flux is linked with the two coils. So, an opposing electromotive force is produced across each coil. This phenomenon is termed mutual inductance.
   The mathematical expression for mutual inductance:
   $\mathrm{M}=\frac{{\mathrm{\mu }}_0{\mathrm{\mu }}_{\mathrm{r}}{\mathrm{N}}_1{\mathrm{N}}_2\mathrm{A}}{\mathrm{L}}$
   Where,${\mathrm{\mu }}_0$ is the permeability of free space,${\mathrm{\mu }}_{\mathrm{r}}$ is the relative permeability of the core, ${\mathrm{N}}_1$is the number of turns in the first coil, ${\mathrm{N}}_2$is the number of turns in the second coil, $\mathrm{A}$ is the cross-sectional area of the smaller coil,$\mathrm{L}$ is the length of the coil.
3. The opposing force of magnetic or current flux linked with the current flow causes the inductance.
4. The magnetic field produced by electric currents moving inside an electrical circuit is what causes inductance.