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What is Lenz’s law about the direction of an induced current?

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The science behind static electricity — electricity Explanation of static electricity and its manifestations in everyday life.

Lenz’s law states that an induced electric current always flows in a direction that opposes the change that induced it. Formulated by the physicist Heinrich Friedrich Emil Lenz in 1834, this principle is fundamental to understanding electromagnetism and is represented by the minus sign in Faraday’s law of induction.12

For example, when a bar magnet is moved toward a coil of wire, the induced current creates a magnetic field that acts to repel the approaching magnet. Conversely, when the magnet is withdrawn, the current reverses to create an attracting force, thereby opposing the change in the magnetic flux.1

This law is essential because it upholds the conservation of energy. If the induced current were to flow in the opposite direction, it would reinforce the change rather than oppose it, which would violate physical laws by spontaneously generating energy.1