| 1. | The effective resistance of an iron cored choke working on ordinary supply frequency is more than its true resistance because of ? | |
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increase in temperature
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capacitance effect between adjacent coil turns
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iron loss in core
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skin effect
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Report Question| 2. | Which of the following is not a non linear element ? | |
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Tunnel diode
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Electric arc
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Gas diode
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Heater coil
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| 3. | The current in a circuit is given by : i = 100 sin 314t amperes The maximum value and frequency of current are ? | |
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100 A, 50 Hz
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70.7A, 50 Hz
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50V2A 100Hz
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100V2A 100Hz
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| 4. | The r.m.s. value of alternating cur rent is given by steady (D.C.) current which when flowing through a given circuit for a given time produces ? | |
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the less heat than produced by A.C. flowing through the same circuit
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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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none of the above
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| 5. | An A.C. voltage of 50 Hz has a maximum value of 50 V. Its value after 1/600 second after the instant the current is zero, will be ? | |
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25 V
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43.3 V
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5 V
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12.5 V
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| 6. | In an A.C circuit, a low value of kVAR compared with kW indicates ? | |
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unity power factor
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maximum load current
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low efficiency
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high power factor
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| 7. | "In any network containing more than one source of e.m.f. the current in any branch is the algebraic sum of a number of individual fictitious currents (the number being equal to the number of sources of e.m.f.), each of which is due to separate action of each source of e.m.f., taken in order, when the remaining sources of e.m.f. are replaced by conductors, the resistances of which are equal to the internal resistances of the respective sources". The above statement is associated with ? | |
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Superposition theorem
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Thevenin's theorem
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Norton's theorem
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None of the above
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| 8. | "In any linear bilateral network, if a source of e.m.f. E in any branch produces a current I in any other branch, then same e.m.f. acting in the second branch would produce the same current I in the first branch". The above statement is associated with ? | |
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reciprocity theorem
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compensation theorem
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superposition theorem
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none of the above
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| 9. | A heater is rated as 230 V, 10 kW, A.C. The value 230 V refers to ? | |
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peak voltage
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average voltage
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r.m.s. voltage
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none of the above
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| 10. | For a voltage source ? | |
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the source e.m.f. and terminal voltage are equal
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terminal voltage is always lower than source e.m.f.
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terminal voltage cannot be higher than source e.m.f.
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None
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