How it works
An inductor is a passive component that stores electrical energy in a magnetic field when electric current flows through it. Because it takes time for the magnetic field to build and collapse, an inductor inherently opposes any rapid changes in current.
In DC circuits, an inductor initially acts as an open circuit when power is applied, but eventually becomes a near-perfect short circuit once the magnetic field stabilizes. In AC circuits, its resistance to alternating current (called reactance) increases as the frequency of the AC signal increases.