# Electrical Engineering Objective Questions { Induction Motors }

330.  For an induction motor, operating at a slip s, the ratio of gross power output to air gap power is equal to

331.  Under no load condition, if the applied voltage to an induction motor is reduced from the rated voltage to half the rated value,

332.  A three-phase cage induction motor is started by direct-on-line (DOL) switching at the rated voltage. If the starting current drawn is 6 times the full load current, and the full load slip is 4%, the ratio of the starting developed torque to the full load torque is approximately equal to

333. In a single phase induction motor driving a fan load, the reason for having a high resistance rotor is to achieve

334.  In a normal 3-phase slip-ring induction motor, the developed starting torque will

335.  A 3-phase induction machine operates on 3-phase fixed frequency ac mains at a per unit slip of 1.5. Consider the following statements regarding the operating condition of the machine 1. It drawn electrical power from the mains. 2. It draws mechanical power through the shaft. 3. It delivers electrical power to the mains. 4. It delivers mechanical power through the shaft. Of these statements :

336. The magnetising current component of the noload current of an induction motor is much larger than a corresponding transformer because of

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