The separation between the plates of a charged parallel-plate capacitor is increased. Which of the following quantities will change?

When we increase the separation between the plates of a charged parallel capacitor the value of Capacitance decreases by the formula

Where,

d=separation between the plates

A=area of plates

ϵ₀=absolute permittivity of vacuum

Charge on the capacitor remains unchanged because no charge transfer takes place.

∴ Potential difference across the capacitor changes by the formula

Where,

Q= charge on the capacitor

C=capacitance

Similarly Energy across the capacitor given by

Where,

C=capacitance

V=potential difference across capacitor

So, as V changes energy stored also changes

Therefore, on increasing separation between the plates of capacitor, potential difference and energy of capacitor changes whereas charge and energy density remains the same.