If the charge on the capacitor is increased by $2 \text{ C}$, the energy stored in it increases by $21 \%$. The original charge on the capacitor is (in $\text{ C}$)

In the circuit shown in the figure,four capacitors are connected to a battery. The maximum energy is stored in the capacitor of.....$\mu F$

The charge $Q$ on a capacitor varies with voltage $V$ as shown in the figure,where $Q$ is taken along the $X$-axis and $V$ along the $Y$-axis. The area of triangle $OAB$ represents

Three identical capacitors are combined in different ways. For the same voltage applied to each combination,the one that stores the greatest energy is:

The energy required to charge a capacitor of $5\,\mu F$ by connecting a $d.c.$ source of $20\,kV$ is......$kJ$.

$A$ parallel plate capacitor of capacitance $1 \ \mu F$ is charged to a potential difference of $20 \ V$. The distance between the plates is $1 \ \mu m$. The energy density between the plates of the capacitor is: