1. The slip at full load for a three-phase induction motor is 0.04 and the rotor current at starting is 5 times its value at full load. Find the starting torque in per unit of full-load torque and the ratio of the maximum torque to full load torque and the slip at which it takes place.
2. A 220-V three phase four-pole 60 Hz squirrel-cage induction motor develops a maximum torque of 250 percent at a slip of 14 percent when operating at rated voltage and frequency. Now, assume that the motor is operated at 180 V and 50 Hz. Determine the maximum torque and the speed at which it takes place.