The self-inductance of the coil may be defined as equal to the e.m.f. induced in volts when the current in the circuit changes at the rate of unit Weber turns.

Self inductance is defined as the induction of a voltage in a current-carrying wire when the current in the wire itself is changing. Self-inductance of a coil is numerically equal to the amount of magnetic flux linked with the coil when unit current flows through the coil.