a. A three-phase, 220-V, 60-Hz induction motor runs at 1,140 r/min. Determine the number of poles (for minimum slip), the slip, and the frequency of the rotor currents.
b. To reduce the starting current, a three-phase squirrel cage induction motor is started by reducing the line voltage to Vs/2. By what factor are the starting torque and the starting current reduced?
Analysis:
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