A parallel plate capacitor is charged from a cell and then isolated from it. The separation between the plates is now increased

Options

A. The force of attraction between the plates will decrease
B. The field in the region between the plates will not change
C. The energy stored in the capacitor will increase
D. The potential difference between the plates will decrease

Answer

B, C

Explanation

`F=qE=(q)(sigma/(2epsilon_0))=q^2/(2epsilonA)`
`q` remains unchanged. Hence,`F` remains unchanged.
`E=sigma/epsilon_0=q/(Aepsilon_0)`
`q` remains unchanged. Hence, `E` also remains unchanged.
`U=q^2/(2C)` or `Uprop1/C`
`C` will decrease. Hence `U` will increase.
`V=Ed` or `Vpropd`
`d` is increasing. Hence `V` will increase.