ADC motor having a series field resistance of 0.25 2 and an armature resistance of 0.15 02, is connected to a 220 V supply and at a particular load runs at 20 rev/s when drawing 20 A from the supply. a) Calculate the e.m.f. generated at this load. b) Determine also the speed of the motor when the load is changed such that the current increases to 25 A. Assume the flux increases by 25 percent.