| 1. | Two coils have inductances of 8 mH and 18 mH and a co-efficient of coupling of 0.5. If the two coils are connected in series aiding, the total inductance will be ? | |
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32mH
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38mH
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40 mH
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48mH
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Report Question| 2. | Which of the following circuit elements will oppose the change in circuit current ? | |
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Capacitance
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Inductance
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Resistance
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All of the above
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| 3. | A laminated iron core has reduced eddy-current losses because ? | |
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more wire can be used with less D.C. resistance in coil
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the laminations are insulated. From each other
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the magnetic flux is concentrated in the air gap of the core
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the laminations are stacked vertically
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| 4. | The magnitude of the induced e.m.f in a conductor depends on the ? | |
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flux density of the magnetic field
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amount of flux cut
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amount of flux linkages
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rate of change of flux-linkages
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| 5. | The direction of induced e.m.f can be found by ? | |
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Laplace's law
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Lens's law
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Fleming's right hand rule
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Kirchhoff's voltage law
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| 6. | A conductor 2 metres long moves at right angles to a magnetic field of flux density 1 tesla with a velocity of 12.5 m/s. The induced e.m.f. in the conductor will be ? | |
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10 V
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15 V
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25 V
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50 V
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| 7. | Two 800 ?H coils in series without mutual coupling have a total inductance of ? | |
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300 ?H
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600 ?H
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150 ?H
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75 ?H
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| 8. | Which of the following is not a unit of inductance ? | |
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Henry
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Coulomb/volt ampere
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Volt second per ampere
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All of the above
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| 9. | Both the number of turns and the core length of an inductive coil are doubled. Its self-inductance will be ? | |
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unaffected
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doubled
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halved
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quadrupled
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| 10. | As per Faraday's laws of electromagnetic induction, an e.m.f. is induced in a conductor whenever it ? | |
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lies perpendicular to the magnetic flux
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lies in a magnetic field
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cuts magnetic flux
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moves parallel to the direction of the magnetic field
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