The plates of a parallel plate capacitor are charged up to $100 \mathrm{V}$. Now, after removing the battery, a $2 \mathrm{m}\mathrm{m}$ thick plate is inserted between the plates. Then, to maintain the same potential difference, the distance between the capacitor plates is increased by $1.6 \mathrm{m}\mathrm{m}$. The dielectric constant of the plate is

Three plates $A, B$ and $C$ each of area $50 \mathrm{c}{\mathrm{m}}^2$ have separation $3 \text{mm}$ between $A$ and $B$ and $3 \mathrm{m}\mathrm{m}$ between $B$ and $C$. The energy stored when the plates are fully charged is

The capacitance of an infinite circuit formed by the repetition of the same link consisting of two identical capacitors, each with capacitance $C$ (figure), is

For section $AB$ of a circuit shown in figure, $C_1=1 \mathrm{\mu F},C_2=2 \mathrm{\mu F},E=10 \mathrm{V}$, and the potential difference $V_A-V_B=-10 V$. Charge on capacitor $C_1$ is:

Three capacitors $A,B$, and $C$ are connected in a circuit as shown in figure. What is the charge in $\mathrm{\mu C}$ on the capacitor $B$?