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1. Assertion (A): In imperfect capacitors, the current does not lead the applied ac voltage by 90°.Reason (R): When subjected to ac fields, the dielectric constant can be expressed as ∈'r - j∈"r.





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  • By: guest on 02 Jun 2017 12.59 am
    Imaginary part of ∈r gives rise to absorption of energy by the material from alternating field. Hence current does not lead the voltage by 90°.
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