Inductor

Definition

An inductor is a passive electrical component that stores energy in a magnetic field when electrical current flows through it. This property of inductors allows them to resist changes in current, making them essential for filtering, tuning circuits, and energy storage in various electronic applications. Inductors are commonly used in transformers, power supplies, and radio frequency applications to manage the flow of electricity and improve circuit performance.

5 Must Know Facts For Your Next Test

1. Inductors are measured in henries (H), with one henry defined as the amount of inductance that produces one volt when the current changes at a rate of one ampere per second.
2. The inductance of an inductor depends on its physical characteristics, including the number of turns in the coil, the core material, and the shape and size of the coil.
3. When current flowing through an inductor is interrupted, it generates a voltage spike due to the collapsing magnetic field, which can be harmful to circuit components.
4. Inductors can be used in combination with capacitors to create filters that allow certain frequencies to pass while blocking others, known as LC circuits.
5. In AC circuits, inductors exhibit reactance, which is a measure of their opposition to alternating current, causing a phase shift between voltage and current.

Review Questions

• How does an inductor function within an electrical circuit and what are its primary uses?
  • An inductor functions by storing energy in a magnetic field when electrical current flows through it. Its primary uses include filtering signals to remove unwanted frequencies, storing energy in power supplies, and acting as a choke to limit changes in current. This ability to resist sudden changes makes inductors critical for maintaining stable operation in various types of electronic circuits.
• What role does an inductor play in creating LC circuits and how do these circuits benefit from its properties?
  • In LC circuits, which consist of inductors and capacitors, the inductor plays a crucial role by providing inductance that works with the capacitance to create resonant frequencies. These circuits benefit from the ability to select specific frequencies for amplification or filtering, allowing for more effective signal processing. The interaction between the stored magnetic energy in the inductor and the stored electric energy in the capacitor enables efficient energy transfer and tuning capabilities.
• Evaluate the implications of voltage spikes caused by inductors when current is suddenly interrupted and discuss methods to mitigate these effects.
  • When current through an inductor is abruptly stopped, it generates a voltage spike due to the sudden collapse of the magnetic field. This spike can damage sensitive components within a circuit or lead to undesired operation. To mitigate these effects, engineers often use flyback diodes, snubber circuits, or varistors that provide alternative paths for the induced current, allowing it to dissipate safely without causing harm to other circuit elements.

Related terms

Capacitor: A passive electronic component that stores energy in an electric field, used to manage voltage fluctuations and filter signals.

Resistor: A component that opposes the flow of electric current, converting electrical energy into heat.

Magnetic Field: A region around a magnetic material or a moving electric charge within which the force of magnetism acts.