| 1. | Lenz's law is a consequence of the law of conservation of ? | |
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induced current
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charge
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energy
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induced e.m.f.
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Report Question| 2. | A coil induces 350 mV when the current changes at the rate of 1 A/s. The value of inductance is ? | |
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3600 mH
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350 mH
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260 mH
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150 mH
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| 3. | A coil is wound on iron core which carries current. The self-induced voltage in the coil is not affected by ? | |
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variation in coil current
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variation in voltage to the coil
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change of number of turns of coil
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the resistance of magnetic path
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| 4. | The co-efficient of coupling between two air core coils depends on ? | |
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self-inductance of two coils only
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mutual inductance between two coils only
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mutual inductance and self inductance of two coils
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none of the above
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| 5. | For a 30 mH inductance (L1) and a 60 mH inductance (L2) The total inductance of L1 and L2 in parallel without mutual coupling will be ? | |
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5mH
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10 mH
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16 mH
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20 mH
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| 6. | Two coils have self-inductances of 10 H and 2 H, the mutual inductance being zero. If the two coils are connected in series, the total inductance will be ? | |
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6 H
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8 H
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12 H
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24 H
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| 7. | The self inductances of two coils are 8 mH and 18 mH. If the co-efficients of coupling is 0.5, the mutual inductance of the coils is ? | |
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4 mH
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5 mH
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6 mH
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12 mH
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| 8. | Which of the following is unit of inductance ? | |
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Ohm
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Henry
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Ampere turns
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Webers/metre
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| 9. | The law that the induced e.m.f. and current always oppose the cause producing them is due to ? | |
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Faraday
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Lenz
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Newton
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Coulomb
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| 10. | Mutually inductance between two magnetically-coupled coils depends on ? | |
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permeability of the core
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the number of their turns
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cross-sectional area of their common core
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all of the above
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