# Inductors in Series

fact
When two or more inductors are in series they can be replaced with a single, equivalent inductor with inductance given by: $$L_{eq} = L_1 + L_2 + ...$$
example

Simplify the circuit below:

This one is straightforward. We have two inductors in series (shocked aren't you?) so we add their inductances to get our equivalent inductance. $$L_{eq} = L_1 + L_2 = 12$$mH $$+ 209$$mH $$= 221$$mH And we're done.
practice problems