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A 3 φ I.M. has synchronous speed of 250rpm and 4% slip at full load. The rotor has a resistance of 0.02Ω/ph and stand still reactance of 0.15Ω/ph. Calculate i) The speed at which max torque is developed. ii) The ratio of maximum to F. L. torque. iii) The ratio of maximum to starting torque.
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