Name: inductors in electric circuits
Uploaded: 2024-04-11T12:48:39.000Z
Duration: 1 min 11 s
Channel: JoVE

K12 Standards

Texas Essential Knowledge and Skills

High School

Chemistry and Physics

IPC.6

IPC.6.A

Inductors

Inductors, often referred to as coils or chokes, play a crucial role in various electronics and power systems.
In essence, any conductor through which an AC current flows inherently possesses inductive properties and could be categorized as an inductor.
To enhance the inductive effect, practical inductors are created by winding a conductive wire around a core made of magnetic material.
When a current flows through an inductor, the voltage across it is directly proportional to the rate of change of the current over time. This proportionality constant is known as the inductance of the inductor, and it is measured in henry.
Inductance opposes abrupt changes in the current flowing through it. So, the current through an inductor cannot change instantaneously.
The physical dimensions, core material, and construction of the inductor determine its inductance.
Inductors come in a variety of values and types, ranging from a few microhenrys to tens of henrys.
They can either be fixed or variable, with cores constructed from a variety of materials including iron, steel, plastic, or even air.

inductors

An inductor is a passive component built to store energy within its magnetic field. It can be fabricated by coiling a wire around a magnetic core. When current is permitted to flow through this inductor, it is observed that the voltage across the inductor is directly proportional to the time rate of change of the current. Mathematically,
<img alt="Inductance formula \(v = L \frac{di}{dt}\) diagram in electromagnetism study." src="/files/ftp_upload/15088/15088_PT_Equation_1.svg" style="text-align: center; height: 36px;" data-altupdatedat="1761848533000" data-alt="Equation1" />
This relationship is expressed using the passive sign convention, where 'L' represents the constant of proportionality, also known as the inductance of the inductor.
The inductance of an inductor is influenced by factors such as its size, the materials used, and the construction method. The unit of measurement for inductance is the Henry (H). Inductance is a measure of the ability of a device to store energy in the form of a magnetic field. Also, it is a characteristic that allows an inductor to resist changes in the current flowing through it.
In addition to being referred to as inductors, these components can also be called coils or chokes. The circuit symbol for an inductor is presented in Figure 1.
<img alt="Electrical circuit diagram, inductor symbol L, current flow i, static equilibrium concept." src="/files/ftp_upload/15088/15088_PT_Figure_1.svg" style="text-align: center; height: 150px;" data-altupdatedat="1761848533000" data-alt="Figure1" />
Figure 2 shows a graphical representation of the relationship between voltage and current for an inductor whose inductance does not depend on the current, also known as a linear inductor.
<img alt="Inductor voltage-current graph, slope L, formula v=L(di/dt), linear relationship, educational chart." src="/files/ftp_upload/15088/15088_PT_Figure_2.svg" style="text-align: center; height: 146px;" data-altupdatedat="1761848533000" data-alt="Figure2" />
A nonlinear inductor, on the other hand, would not have a straight-line plot, as its inductance fluctuates with the current.
Inductors, akin to capacitors, are commercially available in various values and types. In practical applications, inductors typically have inductance values ranging from a few microhenrys, as seen in communication systems, to tens of henrys, as used in power systems. Inductors can either be fixed or variable, and their core can be composed of various materials, including iron, steel, plastic, or even air.

Inductors, often referred to as coils or chokes, play a crucial role in various electronics and power systems.
In essence, any conductor through which an ...

Education

JoVE Core

Electrical Engineering

Unit 1

Energy Storage Elements

KEY TERMS AND CONCEPTS

inductors in electric circuits

Inductors are passive components used in electric circuits to store energy in a magnetic field. They are often made by coiling a wire around a magnetic core. This structure gives the component its inductive behavior and its ability to respond to changing current.

When current flows through an inductor, the voltage across it is proportional to how quickly the current changes with time. This relationship is written using the passive sign convention, and the constant of proportionality is called inductance, or L. Inductance is measured in henrys, written as H.

Inductance depends on several factors. The size of the inductor matters, as do the materials used and the way it is built. This property also describes how well the device stores energy in a magnetic field and how strongly it resists changes in current.

Inductors are also called coils or chokes. Their circuit symbol is used in circuit diagrams to show the component clearly. A linear inductor has a straight-line voltage-current graph because its inductance does not depend on current. A nonlinear inductor does not follow a straight line because its inductance changes with current.

Inductors are sold in many values and types, much like capacitors. Their inductance can range from a few microhenrys in communication systems to tens of henrys in power systems. They may be fixed or variable, and their cores can be made from iron, steel, plastic, or even air.

Inductors in Electric Circuits

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Inductors are passive components used in electric circuits to store energy in a magnetic field. They are often made by coiling a wire around a magnetic core. This structure gives the component its inductive behavior and its ability to respond to changing current. When current flows through an inductor, the voltage across it is proportional to how quickly the current changes with time. This relationship is written using the passive sign convention, and the constant of proportionality is called...

energy stored in inductors

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series and parallel inductors

Equivalent Inductance in Circuit Networks

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key terms and concepts

Learn how inductors store energy in magnetic fields, resist current changes, and differ as linear or nonlinear components in circuits.

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Inductors in Electric Circuits

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