Home | Physics | What is an Electromagnetic Coil?-Definition, Working, Types

What is an Electromagnetic Coil?-Definition, Working, Types

August 30, 2022
written by Adeel Abbas

An electromagnetic coil is a wire in the shape of a coil, spiral, or helix and is used in electrical engineering in applications where electric currents interact with magnetic fields.

What is an Electromagnetic Coil?

One of the simplest electric components is the inductor, which is also known as an Electromagnetic coil. There are two elements, a conductor and a core. The electric conductor is wrapped around the core and is usually made of copper wire.

There is a cycle around the core called a turn. The wire is considered to be a coil when it is turned multiple times. The coil is supposed to provide inductance to the electric circuit. The inductance is an electrical property that affects the flow of current through the circuit.

The advantage of using the coil shape is that it increases the strength of the magnetic field that is produced by a given current. The magnetic fields generated by the separate turns of wire all make their way through the center of the coil to produce a strong field. Because the field lines intersect the circuit multiple, it is possible to increase the voltage in a conductor by winding the wire into a coil.

 How does the Electromagnetic Coil Work?

In order to understand how the inductors work, we should have an imaginary example of an electrical circuit, with a light bulb connected to an inductor and the current going through a switch. When the switch is turned on, the coil will act as a short circuit and that will prevent the light bulb from emitting light because the coil has lower electrical resistance.

The light bulb will be bright at the beginning but will dim to lower light intensity as time goes by. The same effect can be seen when the switch is turned on. Inductance is the reason why this happens. When current is fed through the coil it will create a magnetic field that will try to stop the current from going through the coil.

The current flow goes back to normal after the magnetic field is established. If the current flow is stopped, the magnetic field will generate an electric current through the coil in order to maintain it. The magnetic field can’t be sustained because it collapses A small amount of time is all it will take to illuminate the light bulb.

Windings of an Electromagnetic coil

The core area of the coil is called the magnetic axis, and the wire or conductor which constitutes the coil is called the winding. The ends of the wire are attached to an external circuit when the winding is wrapped around a coil form made of plastic or other material.

A winding with a single tap in the center of its length is called center-tapped and can have more than one winding. A time-varying current through one winding will create a time-varying magnetic field that passes through the other winding, which is said to be magnetically coupled. The primary winding is where the current is applied and which creates the magnetic field. Secondary windings are the other windings that are called the other windings.

Types of Electromagnetic Coil

There are three different types of coil that are designed to operate with different frequencies.

DC Coils

A steady direct current can be found in the windings of direct current coils or electromagnets.

Audio-frequency Coils

An audio frequency range is less than 20 kilohertz, Inductors or transformers operate with alternating currents.


Inductors or transformers work with alternating currents in the radio frequency range of more than 20 KiloHertz.