| 1. | The maximum efficiency of a half wave rectifier is ? | |
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0.3333
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0.4067
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0.6667
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0.729
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Report Question| 2. | To eliminate the crossover distortion, the transistors are given at their bases ? | |
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small forward bias
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self bias
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large current
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smaller current
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| 3. | Static electricity is produced by ? | |
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chemical reaction
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friction
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induction
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both friction and induction
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| 4. | The gain of a CE amplifier is highest at ? | |
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low frequencies
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mid frequencies
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high frequencies
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All frequencies
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| 5. | synchronous motor will stop when ? | |
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load in motor varies
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supply voltage fluctuates
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excitation winding gets disconnected
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supply voltage frequency changes
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| 6. | While starting a synchronous motor as induction motor, field winding is ? | |
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kept open-circuited
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short-circuited by low resistance
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connected to D.C. supply
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None of these
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| 7. | While a synchronous generator is supplying a zero power factor lagging load the armature reaction will be ? | |
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De magnetizing
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Magnetizing
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Cross magnetizing
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Nothing
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| 8. | In a synchronous motor, the negative phase sequence exists when the motor is ? | |
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under-loaded
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supplied with unbalanced voltage
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over-loaded
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None of these
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| 9. | Synchronous motor only runs at ? | |
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less than synchronous speed
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more than synchronous speed
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the synchronous speed
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None of these
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| 10. | If the synchronous motor, properly synchronized to the supply is running on no load and is having negligible loss then ? | |
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the stator current will be very small
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the stator current will be zero
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the stator current will be very high
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the back e.m.f. will be more than the supply voltage
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