The cast steel parallel magnetic circuit in Fig. 11-37 has a 500-turn coil in the center leg, where the cross-sectional area is twice that of the remainder of the core. The dimensions are =1 mm, S= S, = 150 mm', S, = 300 mm', = 40 mm, 6= 110 mm, and = 109 mm. Find the coil current required to produce an air-gap flux of 125 uWb. Assume that S, exceeds S, by 17%. Ans. 1.34 A Fig. 11-37