| 1. | The brush contact losses in a d.c. machine is ? | |
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Inversely proportional to the square of current
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Directly proportional to the square of current
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Inversely proportional to the current
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Directly proportional to the current
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Report Question| 2. | In which transformer, the tertiary winding is used ? | |
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Star - delta
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Star - star
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Delta - delta
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Delta - star
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| 3. | Secondary winding of an auto transformer is also called ? | |
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compensating winding
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common winding
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tertiary winding
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damping winding
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| 4. | The maximum allowable voltage between adjacent segment is ? | |
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10-20V
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20-30V
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40-50V
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30-40V
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| 5. | The field control of a DC shunt motor gives ? | |
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constant torque drive
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constant kW drive
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constant speed drive
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variable load speed drive
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| 6. | The no load current in a transformer is ? | |
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Sinusoidal
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nonsinusoidal
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Trapezoidal
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stepped
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| 7. | Transformer cooling and insulation oil must be of ? | |
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low viscosity
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high viscosity
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low BDV
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low resistivity
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| 8. | Single Phase transformers can be used in parallel only when their voltages are ? | |
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Equal
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Unequal
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Zero
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None of these
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| 9. | When the phase sequence of supply currents are reversed, then the direction of rotation of the resultant magnetic field wave ? | |
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not unchanged
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to and fro
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reversed
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None of these
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| 10. | The availability of full -rated torque at starting is obtained from induction motor is ? | |
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rotor resistance control
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stator voltage control
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slip ring control
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line current control
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