A 100 kW, 460 V shunt generator was run as a motor on no load at its
rated voltage and speed. The total current taken was 9.8 A, including
a shunt current of 2.7 A. The resistance of the armature circuit
(including compoles) at normal working temperature was 0.11 Ω.
Calculate the efficiencies at
(a) full load;
(b) half load.