In the following circuit $C_1=12 \mu F, C_2=C_3=4 \mu F$ and $C_4=C_5=2 \mu F$. The charge stored in $C_3$ is . . . . . $\mu C$.

$n$ small drops, each of capacitance $C$, coalesce to form a single large drop. What is the ratio of the energy stored in the large drop to the energy stored in each small drop?

Each of the $N$ small drops has a radius $r$ and is charged to a potential $V$. If these drops coalesce to form a single large drop,what is the potential of the large drop?

The plates $S$ and $T$ of an uncharged parallel plate capacitor are connected across a battery. The battery is then disconnected and the charged plates are now connected in a system as shown in the figure. The system shown is in equilibrium. All the strings are insulating and massless. The magnitude of charge on one of the capacitor plates is: [Area of plates = $A$]

At a certain distance from a point charge, the electric field is $500\,V/m$ and the electric potential is $3000\,V$. What is this distance in meters?

Five capacitors of $10\,\mu F$ capacity each are connected to a $d.c.$ potential of $100\;V$ as shown in the figure. The equivalent capacitance between the points $A$ and $B$ will be equal to..........$\mu F$.