If the charge on a body is increased by $2 \ C$,the energy stored in it increases by $21 \%$. The original charge on the body in coulomb is:

The energy stored in a capacitor of capacity $C$ which has been raised to a potential $V$ is given by

$A$ variable condenser is permanently connected to a $100 \ V$ battery. If the capacity is changed from $2 \ \mu F$ to $10 \ \mu F$,then the change in energy is equal to:

The total energy stored in the capacitor system shown in the figure will be (in $\mu J$)

$A$ parallel plate capacitor has plate area $A$ and separation between plates is $d$. It is charged to a potential difference of $V_0$ volt. The charging battery is then disconnected and plates are pulled apart to three times the initial distance. The work done to increase the distance between the plates is $(\varepsilon_0 = \text{permittivity of free space})$

$A$ parallel plate air capacitor has a uniform electric field $E$ in the space between the plates. The area of each plate is $A$ and the distance between the plates is $d$. The energy stored in the capacitor is $[\varepsilon_0 = \text{permittivity of free space}]$