Calculating magnetomotive force in a transformer

[bitrex]

If I have a transformer with a known primary inductance and number of turns, and the output is open circuited, how would I go about calculating the magnetomotive force created by the magnetizing current?

 

[Bob S]

You can determine the B field in the transformer by equating the engineering and physics version of the stored energy:
(1/2) L I² = (1/2) ∫ B H dV

where L = inductance, I = current, B = u u₀ H, B=Tesla, H=amp-turns per meter, V = integral over volume of iron, u = relative permeability, u₀ = 4 pi x 10^-7 Henrys per meter..

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