| 1. | In a three-phase induction motor ? | |
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iron losses in stator will be negligible as compared to that in rotor
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iron losses in motor will be negligible as compared to that in rotor
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iron losses in stator will be less than that in rotor
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iron losses in stator will be more than that in rotor
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Report Question| 2. | Insertion of reactance in the rotor circuit ? | |
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reduces starting torque as well as maximum torque
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increases starting torque as well as maximum torque
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increases starting torque but maximum torque remains unchanged
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increases starting torque but maximum torque decreases
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| 3. | In a star-delta starter of an Induction motor ? | |
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resistance is inserted in the stator
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reduced voltage is applied to the stator
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resistance is inserted in the rotor circuit
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applied voltage per stator phase is 57.7% of the line voltage
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| 4. | The possible number of different speeds that can be obtained by connecting two motors in cascade is ? | |
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2
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4
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6
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12
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| 5. | If a 3-phase supply is given to the stator and rotor is short circuited rotor will move ? | |
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in the opposite direction as the direction of the rotating field
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in the same direction as the direction of the field
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in any direction depending upon phase sequence of supply
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all of these
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| 6. | A double squirrel-cage induction motor has ? | |
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two rotors moving in opposite direction
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two parallel windings in stator
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parallel windings in rotor
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two series windings in stator
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| 7. | An induction motor with 1000 r.p.m. speed will have ? | |
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8 poles
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6 poles
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4 poles
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2 poles
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| 8. | The crawling in the induction motor is caused by ? | |
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low voltage supply
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high loads
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harmonics developed in the motor
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improper design of the machine
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| 9. | If any two phases for an induction motor are interchanged ? | |
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the motor will run in reverse direction
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the motor will run at reduced speed
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the motor will not run
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the motor will burn
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| 10. | The 'cogging' of an induction motor can be avoided by ? | |
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proper ventilation
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using DOL starter
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auto-transformer starter
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having number of rotor slots more or less than the number of stator slots (not equal)
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