| 1. | The reactance offered by a capacitor to alternating current of frequency 50 Hz is 20 Q. If the frequency is increased to 100 Hz, reactance becomes ? | |
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5 ?
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10 ?
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16 ?
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30 ?
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Report Question| 2. | An AC. voltage is impressed across a pure resistance of 3.5 ohms in parallel with a pure inductance of impedance of 3.5 ohms ? | |
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the current through the resistance is more
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the current through the resistance is less
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both resistance and inductance carry equal currents
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none of the above
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| 3. | An R-L-C circuit consists of a resistance of 1000 n, an inductance of 100 mH and a capacitance of 10 ?F. The Q-factor of the circuit is ? | |
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10
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20
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50
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100
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| 4. | Which of the following statement is incorrect ? | |
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Ideal voltage source is one whose internal resistance is zero
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Ideal voltage source is one whose internal conductance is zero
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Ideal voltage source is one whose generated voltage is equal to, the available terminal voltage
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Ideal current source is one whose internal conductance is zero
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| 5. | The dual of a loop is ? | |
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twig
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node pair
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mesh
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tree
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| 6. | The reflection coefficient of the simplest standing wave is ? | |
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-1
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1
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zero
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infinity
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| 7. | A pure capacitor connected across an A.C. voltage consumed 50 W. This is due to ? | |
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the capacitive reactance in ohms
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the current flowing in capacitor
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the size of the capacitor being quite big
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the statement is incorrect
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| 8. | Two wattmeters connected to measure the power input to a balanced 3-? circuit indicate 2500 W and 500 W respectively. What is the power factor ? | |
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0.355
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0.455
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0.555
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0.655
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| 9. | In R-L-C series resonant circuit magnitude of resonance frequency can be changed by changing the value of ? | |
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R only
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L only
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C only
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L or C
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| 10. | The r.m.s. value of alternating current is given by steady (D.C.) current which when flowing through a given circuit for a given time produces ? | |
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the more heat than produced by A.C. when flowing through the same circuit
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the same heat as produced by A.C. when flowing through the same circuit
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the less heat than produced by A.C. flowing through the same circuit
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none of the above
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