Inductance

1.   In a circuit resistance offered by an inductor is called inductance.
2.   Henry is unit of inductance.
3.   It is indicated by L.

Inductance in Series

If we connect n inductances in a series the joint effect of all of these inductances is equivalent to the total of individual inductance.

                                    L_eq=   L₁+L₂+L₃+.....+L_n

Inductance in Parallel

we connect  n inductances in a parallel series, the  reciprocal of joint effect of all of these inductances is equivalent to the total of reciprocals of individual inductances.

                                    1/L_eq=  1/L₁+1/L₂+1/L₃+.....+1/L_n