27. Two transformer A and B with identical ratings, are to be designed with fux densities of 1.2 and 1.4 wb/m2 respectively. The weight of transformer A per KVA is(a) More than that of transformer B(b) Less than that of transformer B(c) Equal to that of transformer B(d) None28. Transformer action requires which type of flux?(a) Pulsating magnetic flux(b) Constant(c) Increasing(d) Alternating electric flux29. In what capacity transformer natural oil cooling with tubes is used(a) 3000 KVA(c) 500 KVA(b) 30 KVA(d) 750 KVA30. In full rating of transformer is 90 KW at a pf of 0.9, then its KVA rating is(a) 100(c) 90(b) 150(d) 80
27. (a) More than that of transformer B 28. (a) Pulsating magnetic flux 29. I do not think there is such a limitation on ONAN transformers. 30. (a) 100
