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(b) (i) Explain briefly why an induction motor can never run at synchronous speed? (2 Marks) (ii) If a six-pole induction motor supplied by a three-phase 50 Hz supply has a rotor frequency of 2.3 Hz, Calculate: (a)The percentage slip (b)The speed of the rotor in rpm (4 Marks) (iii)Draw a typical torque versus slip characteristic curve of an induction motor. If rotor resistance is increased show how the new torque versus slip curve deviates from the original one. (4 Marks)

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