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Q4. A three phase, 6 pole, 380 V, 60 Hz induction motor draws a line current of 80 A at a power factor of 0.8 lag with a shaft speed of 19 rev/s. The core losses are 2 kW, the stator winding loss is 1 kW and the windage and friction loss is 1.5 kW.

(a)  Calculate EACH of the following;

(i) The slip;(2)

(ii) The rotor copper loss;(4)

(iii) The shaft output power; (2)

(iv) The efficiency. (3)

(b) Sketch a clearly labelled power-flow diagram for the motor indicating power at each stage. (5)