$A$ capacitor of capacitance $5\,\mu F$ is connected as shown in the figure. The internal resistance of the cell is $0.5\,\Omega$. The amount of charge on the capacitor plate is......$\mu C$.

$(a)$ $A$ $900 \; pF$ capacitor is charged by a $100 \; V$ battery [Figure $(a)$]. How much electrostatic energy is stored by the capacitor?
$(b)$ The capacitor is disconnected from the battery and connected to another $900 \; pF$ capacitor [Figure $(b)$]. What is the electrostatic energy stored by the system?

Find the potential difference $V_a - V_b$ between the points $a$ and $b$ shown in the figure.

$A$ capacitor $C_1 = 1.0 \, \mu F$ is charged up to a voltage $V = 60 \, V$ by connecting it to a battery $B$ through switch $(1)$. Now,$C_1$ is disconnected from the battery and connected to a circuit consisting of two uncharged capacitors $C_2 = 3.0 \, \mu F$ and $C_3 = 6.0 \, \mu F$ in series through a switch $(2)$ as shown in the figure. The sum of the final charges on $C_2$ and $C_3$ is ...... $\mu C$.

Two capacitors are shown in the diagram. Each is charged to potential $V_0$. If capacitor $C$ is filled with a dielectric of constant $2$ and capacitor $2C$ is filled with a dielectric of constant $3$,then the key is closed. The final voltage on the capacitor $C$ will be:

Find the charge on the capacitor $C$ in the following circuit in $\mu C$.