| 1. | Determine the secondary voltage (in V) of a potential transformer when the value of the system voltage is 11,000 V, the turns ratio of the potential transformer is 102 and the percentage voltage error of the transformer is 3 % ? | |
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102.5
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104.6
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108.8
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109.4
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Report Question| 2. | In dc machine iron losses cause ? | |
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heating in core
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loss in efficiency
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rise in temperature of ventilating air
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all of the mentioned
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| 3. | Armature current at starting can be reduced by keeping ? | |
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Rf maximum and Ra minimum
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Ra maximum and Rf maximum
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Ra minimum and Rf minimum
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Ra maximum and Rf minimum
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| 4. | In dc motors, under leading pole tips flux density will ? | |
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increase
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decrease
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either increase or decrease
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None of these
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| 5. | The field winding will be drawn at what degree ? | |
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60 degree
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30 degree
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90 degree
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180 degree
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| 6. | Compensating winding is placed in the ? | |
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pole shoe
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armature core
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main field
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all option are correct
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| 7. | stepped cores are used in transformers in order to reduce ? | |
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volume of iron
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volume of copper
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iron loss
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reluctance of core
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| 8. | In a transformer the resistance between its primary and secondary is ? | |
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zero
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1 ohm
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1000 ohms
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infinite
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| 9. | In a transformer zero voltage regulation is achieved at a load power factor which is ? | |
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zero
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leading
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lagging
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Unity
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| 10. | In the induction motors the torque is directly proportional to the ? | |
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slip^1/3
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higher slip values
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Voltage Slip
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lower slip values
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