| 1. | A synchronous motor has better power factor than an induction motor. This is due to ? | |
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Stator supply is not required to produce magnetic field
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Synchronous motor has no slip
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Mechanical load on the rotor remains constant
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Synchronous motor has large airgap
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Report Question| 2. | When the field circuit of an unloaded salient pole synchronous motor gets suddenly open circuited, then ? | |
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the motor stops
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it runs at a slower speed
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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. | The resultant armature voltage of a synchronous motor is equal to the ? | |
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vector sum of Eb and V
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vector difference of Eb and V
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arithmetic sum of Eb and V
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arithmetic difference of Eb and V
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| 4. | The armature current of a synchronous motor is minimum when operating at ? | |
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unity power factor
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0.707 power factor lagging
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0.707 power factor leading
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zero power factor leading
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| 5. | Why are same types of cells connected in parallel ? | |
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To decrease the voltage rating
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To increase the voltage rating
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To decrease the current rating
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To increase the current rating
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| 6. | There are N resistances, each are connected in parallel having value R with equivalent resistance of X. What will be the total resistance when these N resistances are connected in series ? | |
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NX
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RNX
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X/N
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N²X
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| 7. | Which of the following is equivalent to 0.5 kWh ? | |
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1800000 W
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1800000 J
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18000000 J
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36000000 J
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| 8. | What is the conductivity (in Mhos/m) of a 2 Ohm circular wire, when the length and the diameter of the wire are 10 m and 0.8 m respectively ? | |
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10
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1
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0.1
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5
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| 9. | Erg is a unit of measurement for ? | |
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Energy
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Power
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Voltage
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Impedance
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| 10. | Which of the following quantity will remain the same, when a layer of Teflon is inserted between the plates of a charged parallel plate capacitor ? | |
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Capacitance
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Charge
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Energy of the capacitor
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Potential
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