Note how closely the B-H curve of cast steel in given figure(a) matches the curve for the voltage across a capacitor as it charges from zero volts to its final value.
a. Using the equation for the charging voltage as a guide, write an equation for B as a function of H = [B f(H)] for cast steel.
b. Test the resulting equation at H 900 At/m, 1800 At/m, and 2700 At/m.
c. Using the equation of part (a), derive an equation for H in terms of B [H = f(B)].
d. Test the resulting equation at B = 1 T and B = 1.4 T.
e. Using the result of part (c), perform the analysis of Example, and compare the results for the current I.
EXAMPLE
For the series magnetic circuit of Figure (b).
a. Find the value of I required to develop a magnetic flux of = 4 x 10-4 Wb.
b. Determine µ and µr for the material under these conditions.
