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Q1. | The law that the induced e.m.f. and current always oppose the cause producing them is due to |

A. | Faraday [Wrong Answer] |

B. | Lenz [Correct Answer] |

C. | Newton [Wrong Answer] |

D. | Coulomb [Wrong Answer] |

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⇒ The co-efficient of coupling between two air core coils depends on

self-inductance of two coils only

mutual inductance between two coils only

mutual inductance and self inductance of two coils

none of the above

⇒ 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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⇒ Which of the following circuit element stores energy in the electromagnetic field?

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⇒ A conductor 2 metres long moves at right angles to a magnetic field of flux densit 1 tesla with a velocity of 12.5 m/s. The induced e.m.f. in the conductor will be

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25 V

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aid tite applied voltage

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greater the flux produced by it

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enery

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