Lenz’s Law

Lenz's law is a fundamental principle in the field of electricity that describes the direction of the induced current in a conductor in relation to the changing magnetic flux that caused it. This law was discovered by the German physicist Heinrich Lenz in the 19th century and is considered a corollary of Faraday's law of induction.

Lenz's law states that the induced current in a conductor will always act in such a way as to oppose the change in magnetic flux that caused it. This can be understood by considering a simple example of a coil of wire and a magnet. When the magnet is moved towards the coil, the number of magnetic field lines passing through the coil increases, causing an increase in the magnetic flux. According to Lenz's law, the induced current in the coil will flow in such a way as to create a magnetic field that opposes the increase in magnetic flux.

The induced current creates a magnetic field that is opposite to the field of the magnet, therefore it opposes the change in magnetic flux. This phenomenon is also known as "self-inductance" or "self-induced electromotive force."

The induced current can be represented by the following equation:

EMF = -L * (di/dt)

Where EMF represents the induced electric potential (or "electromotive force" in volts), L is the self-inductance of the coil and di/dt is the rate of change of the current.

Lenz's law has many practical applications, including in the operation of electric motors and generators, in the design of transformers and in electromagnetic devices such as solenoids and relays.