(a) A cast steel ring has a cross-sectional area of 600mm2 and a radius of 25mm. Verify the mmf essential to establish a flux of 0.8mWb in the ring. Use the B-H curve for cast steel.
(b) If a radial air gap 1.5mm wide is cut in the ring of part.
Find the mmf now essential to maintain the similar flux in the ring.