What does Lenz's law state about induced electromotive force (emf)?

Lenz's law is a fundamental principle in electromagnetism that describes the direction of induced electromotive force (emf) and current in a conductor due to a changing magnetic field. According to Lenz's law, the induced emf generates a current that flows in a direction such that it opposes the change in magnetic flux that produced it. This resistance to change is a manifestation of the conservation of energy, ensuring that energy can neither be created nor destroyed.

For example, if the magnetic field in a coil is increasing, Lenz's law states that the induced current will flow in a direction that creates a magnetic field opposing the increase. Conversely, if the magnetic field decreases, the induced current will flow to support and maintain the original magnetic field. This opposition effect is crucial for maintaining the stability of systems in the presence of changing magnetic environments and is a key aspect of inductive components like transformers and inductors.

Understanding Lenz's law is essential for grasping various applications in electrical engineering, such as the operation of electric generators, motors, and inductors, where management of induced currents plays a vital role in the system's efficiency and functionality.