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A parallel plate air capacitor of capaci...

A parallel plate air capacitor of capacitance Cis connected to a cell of emf V and then disconnected from it. A dielectric slab of dielectric constant K, which can just fill the air gap of the capacitor, is now inserted in it. Which of the following is incorrect?

A

The energy stored in the capacitor decreases K times.

B

The change in energy stored is `1/2 CV^2 1/K-1`

C

The charge on the capacitor is not conserved.

D

The potential difference between the plates decreases K times.

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