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A capacitor of capacitance C is charged ...

A capacitor of capacitance C is charged to a potential difference V from a cell and then disconnected from it. A charge +Q is now given to its positive plate. The potential difference across the capacitor is now

A

V

B

`V + (Q)/( C)`

C

`V + (Q)/(2 C)`

D

`V -(Q)/( C)`, if `V lt CV`

Text Solution

Verified by Experts

The correct Answer is:
C
`E=(sigma)/(in_(0))=((Q)/(2)+CV)/(A in_(0)),V=Ed=((Q)/(2)+CV)/((A in_(0))/(d))`
`= ((Q)/(2)+CV)/(C)=V+(Q)/(2C)`.
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Knowledge Check

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