Practice question

**Energy in inductor** cannot change instantaneously because that would require infinite power, current through inductor continuous, voltage may jump, principle used in chokes, inductive kick, back emf, explaining why inductor opposes change in current. The energy ( (1/2) L I² ) is analogous to kinetic energy ( (1/2) m v² ), with inductance acting like mass and current like velocity. Using Φ = B A cosθ, e = -N dΦ/dt = -N A dB/dt = B l v = N B A ω sinωt, L = μ₀ N²A/l, M = e/(dI/dt) and U = ½ L I², result Kinetic energy follows, reflecting Faraday's law and Lenz's opposition.