| 1. | In a synchronous machine, if the field flux axis is ahead of the armature field axis, in the direction of rotation, the machine is working as ? | |
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synchronous generator
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asynchronous generator
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synchronous motor
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asynchronous motor
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Report Question| 2. | The Poter's triangle separates the ? | |
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stator voltage and rotor voltage
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field m.m.f. and armature m.m.f.
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armature leakage reactance and armature reaction m.m.f.
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iron losses and copper losses
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| 3. | In a large generator, dampers ? | |
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reduce frequency fluctuations
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reduce voltage fluctuations
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increase stability
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none of the above
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| 4. | An exciter is a nothing but a ? | |
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10°
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30°
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60°
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90°
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| 5. | A lower voltage alternator, for the same power rating, will be ? | |
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more costly
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large in size
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more efficient
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operating at high r.p.m.
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| 6. | Alternators are usually designed to generate ? | |
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definite currents
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definite power factor
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variable frequencies
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definite frequencies
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| 7. | An exciter for a generator is a ? | |
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shunt motor
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series motor
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shunt generator
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series generator
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| 8. | series generator ? | |
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number of turns in coil
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flux per pole
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frequency of waveform
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all of the above
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| 9. | Which of the following is a prime mover ? | |
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Steam turbine
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Solar energy
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Electric heater
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None of the above
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| 10. | The speed of a 4-pole 60 Hz synchronous machine will be ? | |
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1800 r.p.m.
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2400 r.p.m.
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3000 r.p.m.
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3600 r.p.m.
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