The stator mmf and rotor mmf of a 3-phase induction motor

The stator mmf and rotor mmf of a 3-phase induction motor (A) are equal (B) rotate with slip speed (C) are opposite but rotate with synchronous speed (D) rotate with the same rotor speed 
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a
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A 3-phase induction motor is running at slip ‘s’. If its two supply leads are interchanged, then the operating

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A single-phase induction motor with only the main winding excited would exhibit the following response at

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A 3-phase induction motor is driving a constant torque load at rated voltage and frequency. If both voltage

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Description : The direction of rotation of a 3-phase induction motor is clockwise when it is supplied with 3-phase sinusoidal voltage having phase sequence A-B-C. For counter clockwise rotation of the motor, the phase sequence of the power supply should be  (A) B-C-A (B) C-A-B (C) A-C-B (D) B-C-A or C-A-B

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A three-phase cage induction motor is started by direct-on-line (DOL) switching at the rated voltage. If the

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Description : A three-phase squirrel cage induction motor has a starting torque of 150% and a maximum torque of 300% with respect to rated torque at rated voltage and rated frequency. Neglect the stator resistance and rotational losses. The ... maximum torque is  (A) 13.48% (B) 16.42% (C) 18.92% (D) 26.79%

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Description : A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50 Hz source, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor is  (A) 100 (B) 98 (C) 52 (D) 48

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A three phase slip ring induction motor with chopper controlled resistance has its torque

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