What Is an Inductor?
An inductor is a passive two-terminal electronic component that stores energy in a magnetic field when electric current flows through it. Typically, an inductor consists of an insulated wire wound into a coil, often around a magnetic core made of iron or ferrite.
Section 2: How Inductors Work
An inductor operates on the principle of electromagnetic induction. When the current flowing through the coil changes, the time-varying magnetic field induces a voltage (electromotive force) that opposes the change in current that created it. This property, known as inductance, is the fundamental characteristic of an inductor.
Section 3: A Practical Example
Consider an inductor in a simple circuit with a battery and a switch. When the switch is closed, the current does not instantly reach its maximum value. The inductor resists this change, causing the current to build up gradually. Conversely, if the switch is opened, the inductor's collapsing magnetic field will attempt to keep the current flowing by inducing a large voltage spike.
Section 4: Importance and Applications
Inductors are essential in a wide variety of electronic applications. They are used in power supplies to filter DC output, in radio circuits for tuning to specific frequencies, in transformers to change voltage levels, and in conjunction with capacitors to create resonant circuits for oscillators.