What are Eddy Currents Definition, Eddy Current Loss, Application, FAQs

Edited By Team Careers360 | Updated on Jul 02, 2025 05:04 PM IST

In this article we are going to learn about Eddy current , eddy current definition, eddy current losses, application of eddy current , advantages of eddy current , disadvantages of eddy current, eddy current loss formula and many more.
Note: Eddy current definition in hindi is भंवर धारा

What is Eddy Current/What is meant by eddy current?

When the magnetic flux coupled to the coil changes, induced electromotive force is produced in the coil.

Eddy currents get their name from the fact that they resemble eddies or whirlpools.

Eddy currents are the induced currents that occur when a conductor is placed in a changing magnetic field.

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What are Eddy Currents Definition, Eddy Current Loss, Application, FAQs

Eddy current definition

It can be defined as follows:

According to Faraday's law of induction, eddy currents are the loops of currents that are induced because of the varying magnetic field in the conductor.

The flow of Eddy Currents

The flow of eddy current is perpendicular to the magnetic field inside the conductor.

Principle of Eddy Currents/ Eddy current testing principle:

The Foucault current is another name for an eddy current.

Eddy currents are electric current swirls that are induced within conductors by a changing magnetic field (self-inductance).

The principle of Eddy current is based on Faraday's law of induction.

Self-inductance is how the Eddy Current Principle operates.

It's worth noting that a time-varying magnetic field formed by an AC electromagnet or transformer can cause Eddy currents within neighbouring static conductors.

For example, a magnet and a conductor can move relative to one other (Eddy Current Aluminium).

Eddy Current Magnetic Field

Eddy currents, also known as Foucault's currents, flow in streams where the streams surrounding the conductors pivot in whirls.

The growth of closed rings at a vertical position to the magnetic field's plane is reproduced by fluctuating magnetic fields and development in closed rings (Eddy Current Magnet).

Eddy current flow can occur when a conductor moves through the magnetic field or when the magnetic field that surrounds the stationary channel varies.

This means that everything that occurs in the conductor is subjected to a change in the magnetic field's direction or intensity, which causes the circling current to flow.

The size of this current is proportional to the magnitude of the magnetic field, the circle cross-sectional region, and the flux in the transition, as well as the conductor's resistivity.

This is the Eddy Current Principle at its most basic level.

According to Lenz's law, a swirling or Eddy current creates a magnetic field that opposes the change in the magnetic field that created it, and Eddy Current (whirlpool flows) responds back to the magnetic field's source.

Because of the eddy current created in the surface by the moving magnetic field, a nearby conductive surface will impart a drag force to a moving magnet that opposes its progress.

Related Topics Link,

Some of the applications of Eddy Current:-

Eddy current and its application can be listed as follows:

(1)-The metal to be heated is put in a rapidly fluctuating magnetic field produced by high-frequency alternating current in an induction furnace.

Strong eddy currents form in the metal, generating so much heat that it melts.

This method is used to extract metals from their ore.

The induction furnace is a device that heats metal using a high-intensity induced current.

(2)-Eddy currents can be employed to rotate the rotor in an induction motor.

Eddy currents are formed when a metallic cylinder (or rotor) is placed in a spinning magnetic field.

These currents tend to reduce relative motion between the cylinder and the field, according to Lenz's law.

As a result, the cylinder begins to rotate in the field's direction.

Induction motion works on this concept.

(3)-In an induction motor, eddy currents can be used to rotate the rotor. When a metallic cylinder (or rotor) is placed in a spinning magnetic field, eddy currents develop. These currents reduce the relative motion by rotating the axle in the same direction as the direction of the magnetic field.

Then the cylinder starts to rotate in the direction of the field. This is how eddy current induction motion works.

These are the uses of eddy current class 12/advantages of eddy current class 12.

Also Read:

Eddy current loss in transformer

It is basically I²R loss that is present in the core. Eddy current loss is directly proportional to the conductivity of the core.

eddy current loss formula

P_e=Kf²B²_mt²V

Where,

K- Coefficient of eddy current

f- Frequency of reversal field in Hz

B_m-Maximum value of flux density

t-Thickness of the laminator in meter

V- Volume of magnetic material in m³

These are the information included in eddy current pdf.

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NEET Highest Scoring Chapters & Topics

This ebook serves as a valuable study guide for NEET exams, specifically designed to assist students in light of recent changes and the removal of certain topics from the NEET exam.

Download E-book

NCERT Physics Notes:

Frequently Asked Questions (FAQs)

1. What is eddy current loss/ define hysteresis loss and eddy current loss/eddy current loss definition.

Eddy current loss is conductive I2R loss caused by circulating currents that flow against the core's internal resistance as a result of AC flux linkage.

Hysteresis loss is caused because of the magnetization and demagnetization of the core.

2. What are the uses of eddy current.

1) Induction furnace

2) Dead-beat galvanometer

3) Electric brakes, induction motors

3. What are eddy currents? write their two applications of eddy current.

Eddy current loss is conductive I2R loss caused by circulating currents that flow against the core's internal resistance as a result of AC flux linkage.

Applications:-

1) Induction furnace

2) Dead-beat galvanometer

4. Disadvantages of eddy current

The following are some of the disadvantages of eddy current:

1. Eddy currents cause heat loss in the core of transformers.

2. The eddy current value is greatly dependent on the permeability value.

Detectors have a hard time working as a result of this.

5. How Can Eddy Current Losses Be Reduced?

Eddy currents are a source of energy loss in inductors, transformers, electric engines and generators, and other AC gear, necessitating unusual construction, such as laminated magnetic cores or ferrite cores, to prevent them.

To reduce current losses, the transformer's centre segment is made up of thin laminated collected sheets, and each individual plate is shielded or cleaned.

The Eddy current development is confined to a small percentage of the cross-section area of each unique plate and protected from different plates with this staining.

Along these lines, the current's stream direction reaches a little value.

6. Advantages of eddy current

Eddy Current's Benefits
This method is primarily used in the analysing process.

This is a non-contact analysis method that has no effect on the task.

The analysis is completed in a flash and produces precise results.

The coating surface, which is utilised on a variety of products, is easily examined.

It's even used in a speedometer, as well as in the induction furnace process.

7. Eddy current does not cause____

Sparking

8. What is magnetic damping, and how do eddy currents contribute to it?

Magnetic damping is the reduction of oscillations or motion in a system due to the interaction between a conductor and a magnetic field. Eddy currents contribute to magnetic damping by creating a force that opposes the motion of the conductor through the magnetic field, converting kinetic energy into heat.

9. How do eddy current losses affect the efficiency of electrical devices?

Eddy current losses reduce the efficiency of electrical devices by converting useful electrical energy into wasted heat energy. This can lead to decreased performance, increased power consumption, and potential overheating of the device.

10. What factors influence the strength of eddy currents?

The strength of eddy currents depends on several factors, including:

11. How can eddy current losses be reduced in electrical devices?

Eddy current losses can be reduced by:

12. How do eddy currents affect the magnetic properties of materials?

Eddy currents can affect the magnetic properties of materials by:

13. What are eddy currents?

Eddy currents are circular electric currents induced within conducting materials when they are exposed to a changing magnetic field. These currents flow in closed loops within the conductor, perpendicular to the direction of the magnetic field.

14. How are eddy currents created?

Eddy currents are created when a conductor experiences a change in magnetic flux. This can occur when a conductor moves through a stationary magnetic field, when a magnetic field moves across a stationary conductor, or when the strength of a magnetic field changes over time near a conductor.

15. What is Faraday's law of electromagnetic induction, and how does it relate to eddy currents?

Faraday's law states that a changing magnetic field induces an electromotive force (EMF) in a conductor. This EMF causes eddy currents to flow within the conductor. The magnitude of the induced EMF is proportional to the rate of change of the magnetic flux through the conductor.

16. What is the direction of eddy currents relative to the magnetic field?

Eddy currents flow in closed loops perpendicular to the direction of the changing magnetic field. Their direction is such that they create a magnetic field that opposes the change in the external magnetic field, following Lenz's law.

17. What is Lenz's law, and how does it apply to eddy currents?

Lenz's law states that the direction of an induced current is such that it creates a magnetic field that opposes the change causing it. For eddy currents, this means they generate a magnetic field that opposes the change in the external magnetic field, resulting in a braking effect on the relative motion between the conductor and the magnetic field.

18. What is eddy current loss?

Eddy current loss refers to the energy dissipated as heat within a conductor due to the flow of eddy currents. This loss occurs because the eddy currents encounter resistance within the material, converting electrical energy into thermal energy.

19. What is the skin effect, and how is it related to eddy currents?

The skin effect is the tendency of alternating current to flow near the surface of a conductor. It is related to eddy currents because both phenomena are caused by changing magnetic fields. The skin effect occurs when the changing magnetic field created by the current itself induces eddy currents within the conductor, causing the current to be concentrated near the surface.

20. How are eddy currents used in electromagnetic braking systems?

In electromagnetic braking systems, eddy currents are intentionally induced in a moving conductive material (e.g., a metal disc) by exposing it to a strong magnetic field. The eddy currents create a magnetic field that opposes the motion, resulting in a braking force that slows down the system without mechanical friction.

21. What is the difference between eddy currents and induced currents in a wire loop?

Eddy currents are induced currents that flow in closed loops within a bulk conductor, while induced currents in a wire loop flow through a defined path in a thin conductor. Eddy currents typically result in energy loss as heat, whereas induced currents in a wire loop can be harnessed to generate useful electrical power.

22. How do eddy currents affect the operation of electric motors?

Eddy currents in electric motors can:

23. What is eddy current testing, and how does it work?

Eddy current testing is a non-destructive testing method used to detect surface and near-surface defects in conductive materials. It works by inducing eddy currents in the test material using an alternating magnetic field. Defects or variations in the material's properties disrupt the eddy current flow, which can be detected and analyzed to identify flaws or material characteristics.

24. How are eddy currents used in metal detectors?

Metal detectors use eddy currents by generating an alternating magnetic field that induces eddy currents in nearby metallic objects. These eddy currents create a secondary magnetic field that can be detected by the device. The strength and characteristics of this secondary field provide information about the presence, size, and type of metal object.

25. What is the difference between eddy current losses and hysteresis losses in magnetic materials?

Eddy current losses occur due to the flow of induced currents within the bulk of a conductor, while hysteresis losses are caused by the realignment of magnetic domains within a material as it is magnetized and demagnetized. Eddy current losses are proportional to the square of the frequency of the changing magnetic field, while hysteresis losses are directly proportional to the frequency.

26. How do eddy currents affect the performance of transformers?

Eddy currents in transformers can:

27. What is the relationship between eddy currents and the frequency of the changing magnetic field?

The magnitude of eddy currents increases with the frequency of the changing magnetic field. This is because higher frequencies result in a faster rate of change of magnetic flux, which induces stronger eddy currents. As a result, eddy current losses are proportional to the square of the frequency.

28. How do eddy currents affect the operation of induction heating systems?

In induction heating systems, eddy currents are intentionally induced in the material to be heated. The energy dissipated by these currents is converted into heat, rapidly warming the material. The efficiency and heating pattern depend on the frequency of the alternating magnetic field and the electrical and magnetic properties of the material.

29. What is the principle behind eddy current separators used in recycling?

Eddy current separators use strong alternating magnetic fields to induce eddy currents in non-ferrous metals. These eddy currents create a repulsive force that pushes the metals away from the magnetic field. This allows for the separation of non-ferrous metals from other materials in recycling processes.

30. How do eddy currents affect the design of electrical machines?

Eddy currents influence electrical machine design by:

31. What is the role of eddy currents in electromagnetic shielding?

Eddy currents play a crucial role in electromagnetic shielding by:

32. How do eddy currents affect the performance of electric generators?

Eddy currents in electric generators can:

33. What is the difference between eddy currents in solid conductors and those in laminated structures?

In solid conductors, eddy currents can flow freely in large loops, resulting in significant energy losses. In laminated structures, the thin layers of insulation between conductive sheets restrict the flow of eddy currents to smaller loops within each lamination, reducing overall losses.

34. How do eddy currents contribute to the heating of conductors in alternating current systems?

Eddy currents contribute to heating in AC systems by:

35. What is the relationship between eddy currents and electromagnetic induction?

Eddy currents are a specific manifestation of electromagnetic induction. They are induced currents that occur in bulk conductors when exposed to changing magnetic fields, following the principles of Faraday's law of induction and Lenz's law.

36. How do eddy currents affect the operation of magnetic levitation systems?

In magnetic levitation systems, eddy currents:

37. What is the principle behind eddy current dynamometers?

Eddy current dynamometers use the braking effect of eddy currents to measure power output. A conductive disc or drum rotates in a magnetic field, inducing eddy currents. The resulting braking torque is measured and used to calculate the power being absorbed by the dynamometer.

38. How do eddy currents affect the performance of electrical steels used in transformers and motors?

Eddy currents in electrical steels:

39. What is the relationship between eddy currents and the thickness of a conductor?

The magnitude of eddy currents increases with the thickness of a conductor. Thicker conductors allow for larger eddy current loops, resulting in greater losses. This is why laminated cores, composed of thin sheets, are used to reduce eddy current losses in transformers and motors.

40. How do eddy currents affect the operation of eddy current brakes in roller coasters?

In roller coaster eddy current brakes:

41. What is the principle behind eddy current flow meters?

Eddy current flow meters use the principle that the strength of induced eddy currents in a flowing conductive fluid is proportional to its flow rate. By measuring the changes in the magnetic field caused by these eddy currents, the flow rate can be determined without direct contact with the fluid.

42. How do eddy currents affect the design of wireless power transfer systems?

In wireless power transfer systems, eddy currents:

43. What is the relationship between eddy currents and the conductivity of a material?

The strength of eddy currents is directly proportional to the electrical conductivity of the material. Higher conductivity materials allow for stronger eddy currents, resulting in greater energy losses but also enabling more effective use in applications like eddy current brakes or induction heating.

44. How do eddy currents contribute to the losses in high-frequency transformers?

In high-frequency transformers, eddy currents:

45. What is the principle behind eddy current displacement sensors?

Eddy current displacement sensors work by generating a high-frequency magnetic field that induces eddy currents in a nearby conductive target. The strength of these eddy currents depends on the distance between the sensor and the target. By measuring changes in the sensor's magnetic field caused by the eddy currents, the distance to the target can be determined with high precision.

46. How do eddy currents affect the performance of magnetic resonance imaging (MRI) machines?

In MRI machines, eddy currents:

47. What is the difference between classical and anomalous eddy current losses?

Classical eddy current losses occur in homogeneous materials and can be calculated using standard electromagnetic theory. Anomalous eddy current losses are additional losses that occur in magnetic materials due to domain wall motion and other complex magnetic phenomena. Anomalous losses are often significant in electrical steels and must be accounted for in device design.

48. How do eddy currents affect the operation of electromagnetic flowmeters?

In electromagnetic flowmeters:

49. What is the principle behind eddy current crack detection in aircraft maintenance?

Eddy current crack detection in aircraft maintenance works by:

50. How do eddy currents affect the performance of superconducting magnets?

In superconducting magnets:

51. What is the relationship between eddy currents and the magnetic Reynolds number?

The magnetic Reynolds number is a dimensionless quantity that relates the strength of magnetic advection to magnetic diffusion in a conducting fluid. Higher magnetic Reynolds numbers indicate stronger eddy current effects, which can lead to magnetic field lines being "frozen" into the fluid motion.

52. How do eddy currents affect the design of electromagnetic launchers (railguns)?

In electromagnetic launchers:

53. What is the principle behind eddy current retarders used in heavy vehicles?

Eddy current retarders in heavy vehicles work by: