Two condensers of capacities $1\,\mu F$ and $2\,\mu F$ are connected in series and the system is charged to $120\,V$. Then the potential difference $(P.D.)$ across the $1\,\mu F$ capacitor (in $volts$) will be

Which of the following combinations of $7$ identical capacitors each of $2 \mu F$ gives a resultant capacitance of $\frac{10}{11} \mu F$?

In the following circuit,the resultant capacitance between $A$ and $B$ is $1\,\mu F$. Then the value of $C$ 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 $J$)

Five capacitors are connected to a $DC$ potential of $100\,V$ as shown in the figure. Find the charge in the $10\,\mu F$ capacitor (in $\mu C$).

Two parallel plate capacitors are connected in series. Each capacitor has a plate area $A$ and a separation $d$ between the plates. The dielectric constants of the media between their plates are $2$ and $4$. The separation between the plates of a single air capacitor of plate area $A$ which effectively replaces the combination is: