Hello all, I do apologize if this is in the wrong section as this is my first post. If I have posted in the wrong area please let me know. I have a basic understanding of the concept of inductance but have read many formulas which I think are trying to express the same idea but from various sources. I would like to put my understanding forward and have it corrected where need be. Faraday law determines the amount of emf (Voltage) which will be induced by a coil of wire into an electromagnetic field. emf (voltage induced) = -N Δ[itex]\Phi[/itex] / Δt where N = number of turns in the coil [itex]\Phi[/itex] = Flux density (BA) measured in Teslas B = I think this depends on the type of coil, for a solenoid B = Mo n I where Mo = 4pi x 10-7 n = number of turns in coil / length of the coil I = current A = Cross sectional area of the coil (pi r2) t = time There are a few variables I would think may be a factor in this equation which are not included. Firstly the permeability of the core and secondly the frequency at which the magnetic field changes. Any help in understand these equations would be greatly appreciated. Thankyou.