What does Faraday's law of electromagnetic induction state?

Faraday's law of electromagnetic induction states that the induced electromotive force (emf) in any closed circuit is proportional to the rate of change of magnetic flux through that circuit. This principle reveals how a changing magnetic field can create an electric current in a conductor. Specifically, when the magnetic field within a loop changes, the magnetic flux — which is the product of the magnetic field strength and the area through which it passes — also changes, inducing an emf that drives current through the circuit. This is a fundamental concept in electromagnetism and explains how generators and transformers operate.

The other options do not accurately describe Faraday's law. For instance, while current and induced emf are related, the law does not state that the induced emf is proportional to the current—it specifically relates to the change in magnetic flux. The idea that the magnetic field does not change with current is a separate concept that does not apply to Faraday's law directly. Additionally, the dependence of the induced voltage on resistance is not a part of Faraday's law; instead, it focuses on the rate at which the magnetic flux changes rather than circuit resistance factors. Thus, the correct understanding of the law is crucial for grasping how electromagnetic induction works in practical applications.