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How does Faraday’s law explain electromagnetic induction?

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Faraday’s law of induction is a fundamental principle in physics that provides the quantitative basis for electromagnetic induction. It states that a changing magnetic field passing through a circuit induces an electromotive force (emf) within that circuit.12

The law is expressed by the equation:
$e m f = - \frac{d Φ}{d t}$

In this relationship, $Φ$ represents the magnetic flux—a measure of the total magnetic field penetrating the area of the circuit—and $t$ represents time. The magnitude of the induced emf is directly proportional to the rate at which this magnetic flux changes over time.12

The negative sign in the equation is a mathematical expression of Lenz’s law, which dictates that the induced current will flow in a direction that opposes the change in magnetic flux that created it. This ensures the conservation of energy, as the induced current acts to maintain the stability of the system. Faraday’s law is essential to modern technology, serving as the foundation for the power industry, electric motors, and transformers.324