Two capacitors $C_1$ and $C_2$ in a circuit are joined as shown in the figure. The potential of point $A$ is $V_1$ and that of point $B$ is $V_2$. The potential at point $D$ will be

Two equal capacitors are first connected in series and then in parallel. The ratio of the equivalent capacities in the two cases will be

Three equal capacitors,each with capacitance $C$,are connected as shown in the figure. The equivalent capacitance between $A$ and $B$ is:

$A$ $5 \mu F$ capacitor is connected in series with a $10 \mu F$ capacitor. When a $300 \ V$ potential difference is applied across this combination,the total energy stored in the capacitors is (in $J$)

$A$ capacitor is made of a flat plate of area $A$ and the second plate has a staircase-like structure. The width of each stair is $a$ and its height is $b$. The total width of the plate is $2a$. The distance between the flat plate and the first part of the staircase is $d$. Find the capacity of the capacitor.

Three capacitors $3 \mu F$,$6 \mu F$,and $6 \mu F$ are connected in series to a source of $120 V$. The potential difference,in volts,across the $3 \mu F$ capacitor will be: