| 1. | ln a highly capacitive circuit ? | |
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actual power is greater than reactive power
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reactive power is greater than actual power
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apparent power equals actual power
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actual power equals reactive power
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Report Question| 2. | Which of the following values of alternating voltage should an insulation absolutely withstand ? | |
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The average value
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The r.m.s. value
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The peak value
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Half the effective value
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| 3. | Wire-wound resistors are unsuitable for use at high frequencies because they ? | |
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create more electrical noise
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are likely to melt under excessive eddy current heat
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consume more power
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exhibit unwanted inductive and capacitive effects
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| 4. | All definitions of power factor of a series R-L-C circuit are correct except ? | |
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ratio of net reactance and impedance
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ratio of kW and kVA
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ratio of R and Z
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ratio of W and VA
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| 5. | The double energy transient occur in the ? | |
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purely inductive circuit
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R-L circuit
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R-C circuit
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R-L-C circuit
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| 6. | The time constant of the capacitance circuit is defined as the time during which voltage ? | |
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falls to 36.8% of its final steady value
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rises to 38.6% of its final steady value
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rises to 63.2% of its final steady value
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none of the above
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| 7. | Capacitive reactance is more when ? | |
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capacitance is less and frequency of supply is less
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capacitance is less and frequency of supply is more
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capacitance is more and frequency of supply is less
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capacitance is more and frequency of supply is more
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| 8. | A 100 kW three phase delta connected motor works on a supply of three phase 3.3 kV. The motor efficiency is 92% and the power factor is 90%. The line current drawn by the motor will be ? | |
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10 A
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15 A
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18 A
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21 A
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| 9. | ln a series R-L-C circuit, the voltage across inductance will be maximum ? | |
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at resonance frequency
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just before resonant frequency
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just after resonant frequency
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none of the above
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| 10. | A parallel A.C. circuit in resonance will ? | |
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have current in each section equal to the line current
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have a high voltage developed across each inductive and capacitive section
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act like a resistor of low value
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have a high impedance
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