Exam Question

(a) List the factors that determine the maximum developed torque of the induction motor. (6)

(b) The primary and secondary windings of a 500 kVA transformer have resistances of 0.42 Ω and 0.0019 Ω respectively. The primary and secondary voltages are 11 000 V and 415 V respectively and the core loss is 2.9 kW, assuming the power factor of the load to be 0.8. Calculate the efficiency on: (10)

(i) Full load

(ii) Half load;