| 1. | A PMMC type voltmeter, having a full scale reading of 250 V and an internal resistance of 400 kilo-ohms, is connect with a series resistance of 100 kilo- ohms. Calculate the sensitivity of the voltmeter (in Ohms/Vols) ? | |
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2400
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2000
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20000
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24000
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Report Question| 2. | Determine the percentage voltage error of a potential transformer with the system voltage of 11,000 V and having a turn's ratio of 104, if the measured secondary voltage is 98 V ? | |
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7.35
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575
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6.25
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8.84
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| 3. | A circuit having power factor of 0.8 consumes 40 W. What will be the value of reactive power (in VAR) of the circuit ? | |
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20
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40
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30
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10
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| 4. | Determine the phase angle (in degrees) of a balanced 3-phase star connected system, if the first and the second wattmeter show readings of 200 W and 1200 W respectively ? | |
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51
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65
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78
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84
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| 5. | Which one of the following statement is NOT true about PMMC type instruments ? | |
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PMMC type instruments have uniformly divided scale.
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These instruments are suitable for both AC and DC currents.
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Stray magnetic errors are small in these types of instruments.
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The cost of PMMC instruments is high.
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| 6. | Which one of the following instrument can measure voltage, resistance, and current ? | |
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Ammeter
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Voltmeter
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Multimeter
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Wattmeter
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| 7. | For a dc machine shunt resistance and armature resistance values are ? | |
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high and high
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high and low
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low and low
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low and high
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| 8. | If the field of a dc shunt motor gets opened while the motor is running, then the ? | |
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motor will become slow.
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motor will attain dangerously high speed
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armature current will drop
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armature will oscillate about original speed as the mean speed
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| 9. | Inter pole winding is connected in ? | |
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series with armature
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series with main poles
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parallel with armature
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parallel with main poles
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| 10. | In large machines flat copper strips know as ? | |
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windings
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bushes
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risers
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either of these
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