| 1. | If resistance is 20? and inductance is 2H in a R-L series circuit, then time constant of this circuit will be ? | |
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0.001 s
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0.1 s
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10 s
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100 s
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Report Question| 2. | What will be the phase angle between two alternating waves of equal frequency, when one wave attains maximum value the other is at zero value ? | |
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0º
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46º
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90º
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180º
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| 3. | In an A.C. circuit I sin ? is called ? | |
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active component
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wattless component
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any of the above
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none of the above
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| 4. | The dynamic impedance of an R-L and C parallel circuit at resonance is ...... ohm ? | |
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R/LC
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C/LR
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LC/R
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L/CR
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| 5. | For a series R-L-C circuit tuned at resonant frequency which of the following statements is correct ? | |
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The voltage across inductance is greater than applied voltage
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The voltage across capacitance is greater than applied voltage
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The voltage across both inductance and capacitance is greater than applied voltage
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The voltage across both inductance and capacitance is less than the applied voltage
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| 6. | The reactance offered by a capacitor to alternating current of frequency 50 Hz is 20 ?. If frequency is increased to 100 Hz, reactance becomes ...... ohms ? | |
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2.5
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5
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10
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15
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| 7. | If two sinusoids of the same frequency but of different amplitudes and phase angles are subtracted, the resultant is ? | |
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a sinusoid of the same frequency
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a sinusoid of half the original frequency
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a sinusoid of double the frequency
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not a sinusoid
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| 8. | Two waves of the same frequency have opposite phase when the phase angle between them is ? | |
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360º
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180º
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90º
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0º
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| 9. | A sine wave of voltage varies from zero to maximum of 200 V. How much is the voltage at the instant of 30º of the cycle ? | |
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50 V
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82.8 V
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100 V
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173.2 V
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| 10. | The r.m,s. value of a half-wave rectified current is 100 A Its value for full-wave rectification would be ...... ampere ? | |
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141.4
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200
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200/ ?
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40/ ?
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