Faraday’s law is a law of electromagnetism that predicts the interaction of a magnetic field with an electric circuit to produce EMF (electromagnetic induction). It is also called electromagnetic induction. 

This law is named after Michael Faraday, who experimented with a magnet and a coil. 

In this experiment, he noticed that EMF is induced when the flux passing through the coil changes. Two laws are derived from Faraday’s law of electromagnetic induction. 

The first law describes the production of electromotive force. The second law calculates the electromotive force induced in the conductor. 

Faraday’s Experiment

Faraday carried out an experiment with a magnet and a coil. He took a magnet and connected it to a galvanometer across the coil. 

At the beginning, when the magnet was at rest, the galvanometer needle shows no deflection. 

Now, when he directs the magnet toward the coil, the needle of the galvanometer shows deflection in one direction. When the magnet was at rest at that position, the needle of the galvanometer returned to zero position and showed no deflection.

When the magnet was moved again, there was some deflection in the galvanometer but in the opposite direction. When he held the magnet stationary once again, there was no deflection. He noticed that if the magnet is held stationary, and the coil moves towards the magnet, the galvanometer shows deflection. He also saw that the emf induction is greater if he changes the magnetic field faster. 

Faraday discovered that the flux linkage with a coil changes whenever there is a motion between a conductor and a magnetic field, and this causes the induction of emf or voltage across a coil. 

Faraday’s law of electromagnetic induction

Faraday’s law shows how a change in magnetic fields can cause the flow of current in a wire. Based on this experiment, Faraday stated two laws. 

Faraday’s first law 

An induced EMF is produced whenever there is any change in the magnetic field of a coil. If the conductor circuit is closed, the current will also move inside the circuit. This current is named induced current. 

We can change the magnetic field easily by:

• Moving a magnet towards or away from the coil.
• Moving the coil inside or outside of the magnetic field.
• Changing the area of the coil.
• Rotating the coil. 

Faraday’s second law

This law says that the rate of change of flux that links with the coil is equal to the magnitude of EMF produced in the coil. 

Examples of Faraday’s law

Applications of Faraday’s law are listed below:

•  Power transformers are an example of Faraday’s law as they work on the principle of mutual induction. 
• The induction cooker also works on the law of mutual induction. A copper wire is placed below a cooking container. When the current flows through the coil, it produces a change in a magnetic field. The change in the magnetic field induces current, and it produces heat.
• An electromagnetic flow metre is used to calculate the velocity of the flow of liquids.
• It is used in instruments like guitar, violin etc.
•  It also applies to medical instruments like MRI scans, X-ray machines and CT scans. 
• Maxwell’s equation, which describes how the change in magnetic field also changes the electric field, is also based on Faraday’s law. 
• In Physics, Faraday’s law further deepened the connection between the phenomenon of electricity and magnetism.

Conclusion

In this article, we studied Faraday’s law of electromagnetic induction and the definition of Faraday’s law. Faraday’s law predicts the interaction of a magnetic field with an electric circuit to produce EMF (electromagnetic induction). Then we discussed Faraday’s experiment where he carried out an experiment with a magnet and a coil. Based on this experiment, he discovered two laws. We also learnt about his laws in detail. We also discussed how Faraday’s law implies physics along with its examples.