| 1. | For the full wave rectified sine wave the r.m.s. value is ? | |
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0.707 Imax
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0.636 Imax
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0.318 Imax
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zero
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Report Question| 2. | Power factor of an electrical circuit is equal to ? | |
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R/Z
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cosine of phase angle difference between current and voltage
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kW/kVA
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all above
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| 3. | all above ? | |
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more than resonant frequency
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less than resonant frequency
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resonant frequency
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none of the above
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| 4. | The voltage of domestic supply is 220 V. This value represents ? | |
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mean value
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r.m.s. value
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peak value
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average value
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| 5. | Magnitude of current at resonance in R-L-C circuit ? | |
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depends upon the magnitude of R
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depends upon the magnitude of L
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depends upon the magnitude of C
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depends upon the magnitude of R, L and C
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| 6. | ln a series resonant circuit, the impedance of the circuit is ? | |
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minimum
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maximum
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zero
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none of the above
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| 7. | For a purely resistive circuit the following statement is in correct ? | |
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Work done is zero
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Power consumed is zero
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Heat produced is zero
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Power factor is unity
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| 8. | The ability of a resonant circuit to discriminate between one particular frequency and all others is called its ? | |
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impedance
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selectivity
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conductance
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none of the above
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| 9. | Poor power factor ? | |
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reduces load handling capability of electrical system
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results in more power losses in the electrical system
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overloads alternators, transformers and distribution lines
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result in all above
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| 10. | The time constant of a series R-C circuit is given by ? | |
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R/C
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RC²
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RC
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R²C
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