| 1. | Slip-rings in a synchronous motor carry ? | |
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direct current
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alternating current
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no current
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all of the above
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Report Question| 2. | If the field circuit of an unloaded salient pole synchronous motor gets suddenly open-circuited, then ? | |
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it runs at a slower speed
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the motor stops
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it continues to run at the same speed
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it runs at a very high speed
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| 3. | Which of the following motors is non self starting ? | |
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D.C. series motor
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Synchronous motor
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Squirrel cage induction motor
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Wound round induction motor
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| 4. | Which of the following losses, in a synchronous motor, does not vary with load ? | |
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Windage loss
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Copper losses
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Any of the above
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None of the above
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| 5. | Asynchronous motor which works on a leading power factor and does not drive a mechanical load is called as ? | |
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static condenser
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condenser
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synchronous condenser
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none of the above
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| 6. | The angle between the rotor poles and stator poles, in a synchronous motor, is known as ? | |
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power factor angle
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torque angle
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synchronizing angle
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angle of retardation
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| 7. | The coupling angle or load angle of synchronous motor is defined as the angle between the ? | |
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rotor and stator teeth
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rotor and the stator poles of opposite polarity
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rotor and the stator poles of the same polarity
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none of the above
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| 8. | The construction of a synchronous motor resembles ? | |
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a series motor
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an induction motor
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an alternator
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a rotary converter
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| 9. | By which of the following methods the constant speed of a synchronous motor can be changed to new fixed value ? | |
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By changing the supply frequency
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By interchanging any two phases
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By changing the applied voltage
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By changing the load
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| 10. | In synchronous motor, the magnitude of stator back e.m.f Eb depends on ? | |
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load on the motor
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d.c. excitation only
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both the speed and rotor flux
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none of the above
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