Magnetic Field and Induction?

📌 CONCEPT: Electromagnetic induction is the process by which a changing magnetic field in a coil induces an electric current through the movement of electrons in the coil's conductor.

📐 RULE / FORMULA: According to Faraday's law of electromagnetic induction, the direction of the induced current is determined by Lenz's law, which states that the induced current flows in a direction such that it opposes the change in the magnetic flux.

💡 WORKED EXAMPLE: A circular loop of wire is placed in a varying magnetic field generated by an AC generator. As the south pole of the magnet approaches the loop, the magnetic flux increases, inducing a current in the loop. According to Lenz's law, the direction of the induced current is such that it opposes the increase in the magnetic flux, resulting in a clockwise current flow. As the south pole recedes, the magnetic flux decreases, and the direction of the induced current reverses, resulting in a counterclockwise current flow.

⚠️ COMMON MISTAKE: Students often confuse the direction of the induced current with the direction of the magnetic field, forgetting to apply Lenz's law to determine the correct direction of the induced current.