1. Find the synchronous impedance and reactance of a 1-phase of 200 A on short-circuit and a generated e.m.f. of 50 V on open- alternator in which a given field current produces an armature current circuit. The armature resistance is 0.1 ohm. To what induced voltage must the alternator be excited if it is to deliver a load of 100 A at a p.f. of 0.8 lagging, with a terminal voltage of 200 V.