shorts notes of physics ch 6

This chapter on Electromagnetic Induction explains how changing magnetic flux produces an induced electromotive force (emf). It begins with magnetic flux, defined as Φ=B⋅Acos⁡θ, and introduces Faraday’s laws, which state that emf is induced whenever flux changes, with its magnitude proportional to the rate of change. Lenz’s law adds that the induced emf always opposes the cause producing it, ensuring conservation of energy.

The notes cover motional emf, generated when a conductor moves across a magnetic field, and emf in rotating coils. The concepts of self-induction and mutual induction are explained, showing how circuits resist changes in current and how coupled coils influence each other. Applications include solenoids, where inductance depends on geometry and permeability, and superconducting loops, which maintain constant flux.

Finally, the chapter explores growth and decay of current in L-R circuits, introducing the time constant τ=L/R, and energy storage in inductors. Together, these principles form the foundation for understanding transformers, generators, and modern electrical systems.