The amount of work done in increasing the voltage across the plates of a capacitor from $5 V$ to $10 V$ is $W$. The work done in increasing it from $10 V$ to $15 V$ will be

$A$ parallel plate capacitor having plate area $A$ and separation $d$ is charged to a potential difference $V$. The charging battery is disconnected and the plates are pulled apart to four times the initial separation. The work required to increase the distance between the plates is ($\epsilon_0 =$ permittivity of free space).

$A$ $10 \, pF$ capacitor is connected to a $50 \, V$ battery. How much electrostatic energy is stored in the capacitor?

The mean electric energy density between the plates of a charged capacitor is (here $q$ = charge on the capacitor and $A$ = area of the capacitor plate).

$A$ capacitor has a capacity of $2\,\mu F$ and is charged to a voltage of $50\,V$. The energy stored is:

Which formula gives the energy stored in a charged capacitor?