Eddy Currents FAQs

What are eddy currents?

Based on Faraday’s law of induction, eddy currents are small circular current loops formed within a conductor by the changing magnetic field around the conductor.

What are the applications of eddy currents?

• Braking in trains and amusement rides
• Speedometers
• Induction cookers
• Non-destructive testing

How are eddy currents produced?

Eddy currents are generated inside a conductor when it moves through a magnetic field or when the magnetic flux flowing through it varies continuously.

How can eddy currents be minimized?

Eddy currents can be minimized by:

• Laminating the metal core, eddy currents can be reduced.
• Using magnetic materials with a high electrical resistance value.

What are the factors on which the magnitude of eddy current depends?

The eddy current’s magnitude is:

• Proportional to the magnetic field’s magnitude
• Proportional to the area of the loop
• Proportional to the rate of change of magnetic flux inversely
• Proportional to the conductor’s resistance

Why are Eddy currents undesirable?

When a conductor is moved in a magnetic field, eddy currents are generated. Eddy currents cause energy to be lost as heat. It can cause power loss and lower efficiency in electric motors, generators, and even transformers. These currents may cause the equipment to degrade.

Eddy currents are whirling currents produced in a conductor by a changing magnetic field. They are a fundamental phenomenon in electromagnetism, resulting from Faraday’s law of electromagnetic induction, which states that a changing magnetic field generates an electromotive force (EMF) and, eventually, an electric current in a nearby conductor. This phenomenon is first discovered by the physicist Leon Foucault in 1855 and is also called Foucault’s Currents (as Foucault’s discovered this phenomenon).

In this article, we will learn in detail about eddy current, its applications, and how to minimize it.