Lenz’s law states that the direction of the induced electric current by a changing magnetic field in a conductor in such a way that the induced current creates a magnetic field that opposes the changes of the initial magnetic field. It was named after Emil Lenz who stated this law in 1834.
Lenz’s law has many uses. It is a qualitative law that identifies the direction of an induced current, and at the same time, cannot say anything about its magnitude. It helps in predicting many of the directions of electromagnetism, such as the induced voltage in a wire loop or an inductor by a current that is changing, and also the drag force of eddy currents inserted in a magnetic field over a moving object.
Faraday’s law is a law that is very basic to electromagnetism. This helps in predicting how an electric circuit will interact with a magnetic field to produce an emf (electromotive force). This phenomenon is known as electromagnetic induction. Faraday’s law is the main operating principle of inductors and transformers and many other types of motors.
Differences between Lenz’s law and Faraday’s Law
Lenz’s law | Faraday’s law |
Lenz’s law provides information about the direction the current will flow. | All the information about Faraday’s law is given by the magnetic field of emf when it is produced. |
This law is a version of Faraday’s law. | This law is not a version of Lenz’s law. |
Emf is induced from Faraday’s law, then it causes Lenz’s law when the production direction opposes. | Emf is induced from Lenz’s law, then it causes Faraday’s law when the production direction is not opposed. |
The direction voltage and an induced current are the same as the conductor in any loop. | Only the induced current and voltage change in any magnetic field. |
Lenz’s law of electromagnetic induction is more important than the conservation of energy. | Based on Faraday’s law, the conservation of electrical energy changes to mechanical energy. |
Lenz’s law equation: ϵ = -NdΦB/dt | Faraday’s law equation: ϵ = -dΦB/dt |
How exactly does Faraday’s law relate to Lenz’s law?
The exact relation between Lenz’s law and Faraday’s law is explained below:
- In electromagnetism, Lenz regulated the articulation that a real electric current flows towards the path. This flow is to such an extent that when it is incited, the flow goes against the change.
- In 1834, a Russian physicist named Heinrich Friedrich Emil Lenz reasoned this regulation.
- The regulation of Emil Lenz says that as per Faraday’s law by an adjustment of attractive motion when an emf is created, the real emf has an extremity which is such that a current is being delivered which produces it whose attractive field goes opposite to the change.
- The rule of electromagnetic enlistments was given by Faraday’s regulation.
Application of Lenz’s law
There are many applications of Lenz’s law.
- This law shows that the induced electromotive force and the flux change have opposite signs and provides a physical interpretation of the sign selection in Faraday’s induction method.
- Lenz’s law also applies to generators. When a current is induced in the generator, the direction of this induced current is to rotate the generator against the generator (according to Lenz’s law). Therefore, the generator requires more mechanical energy. Lenz’s law is also used in electromagnetic brakes and induction cooktops.
- The place where Lenz’s law is used in physics, we would need to take a look at the metal detectors and braking system of the train, along with the microphones and card readers.
- Application of Lenz’s law is also seen in the field of physics in electric generators and ac generators.
Application of Faraday’s law
There are many applications of Faraday’s law-
- Based on Faraday’s law, electrical types of equipment like transformers work on
- Based on mutual induction, the induction cooker works. This is the principle of Faraday’s law.
This principle is valid for many gadgets like-
- Electric generators
- Transformers
- Corridor effect metres
- Current clamp
- Enlistment cooking and engines
- Electromagnetic shaping
- Attractive stream metres
Conclusion
A change in the magnetic field we saw with Lenz’s law will induce a current in such a way that the induced current will also induce a magnetic flux in which the change of magnetic field is counteracted.
We came to know about transformers where we saw that power is constant when we drop the voltage and then raise the current, which depends on whether the loops on the end are less or more when we are transferring it.
In a loop by a changing magnetic field, an electric current can be induced. Only when the magnetic field in the loop changes through the loop. The flux must be changing only; the existence of the magnetic field to produce the induced emf is not sufficient.