A mild steel ring, of constant relative permeability 600, is wound with a coil of 300 turns. The ring has a mean circumference of 150 mm and a uniform cross-sectional area of 500 mm2 . Determine the...

A mild steel ring, of constant relative permeability 600, is wound with a coil of 300 turns. The ring has a mean circumference of 150 mm and a uniform cross-sectional area of 500 mm2 . Determine the current necessary to produce a fux of 0.5 mWb in the ring.