An air capacitor is completely charged upto the energy U and removed from battery. Now distance between plates is increased slowly by an external agent. If work done by external agent is 3U then ratio of final separation between the plates to the initial separation :

An air capacitor is completely charged upto the energy U and removed f

1.	An air capacitor is completely charged upto the energy U and removed from battery. Now distance between plates is increased slowly by an external agent. If work done by external agent is 3U then ratio of final separation between the plates to the initial separation :
Answer» 5 4 3 `1.5` Solution :INITIALLY, `U=(q^(2))/(2C)=(q^(2))/(2KC_(0))`....(i) When di-electric is pulled out, then `U + 3U = (q^(2))/(2C_(0))` `4U = (q^(2))/(2C_(0))`….(ii) Then, (ii) & (i) `rArr K = 4`.

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An air capacitor is completely charged upto the energy U and removed from battery. Now distance between plates is increased slowly by an external agent. If work done by external agent is 3U then ratio of final separation between the plates to the initial separation :

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