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A parallel plate capacitor is connected ...

A parallel plate capacitor is connected to a battery as shown in figure .Consider two situations ,
(A) Key K is kept closed and plates of capacitors are moved apart using insulating handle.
(B) Key K is opened and plates of capacitors arc moved apart using insulating handle. Choose the correct optlons.
,

A

In A : Q remains same but C changes.

B

In B : E remains same but C changes.

C

In A : E remains same and hence Q changes.

D

In B : Q remains same and hence E changes.

Text Solution

Verified by Experts

The correct Answer is:
C, D
When the K is closed and the space between the plate of capacitor increases, the capacitance decrease by relation `C = (in_(0)A)/(d)` but battery remains same so potential difference across plate remains V same. So, by `C = (Q)/(V)` , Q decrease and option (C ) is correct.
By situation (B), when K is open and capacitor separated from battery and hence Q remains same and by increasing the distance between two plates C is decreases according to
`C= (in_(0)A)/(d) ` but in `C = (Q)/(V)` when Q decreases V increases hence option (D) is correct.
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