A parallel plate capacitor is connected to a battery. The plates are pulled apart with a uniform speed. If $x$ is the separation between the plates, the time rate of change of electrostatic energy of capacitor is proportional to

A capacitor of capacitance $6\,\mu \,F$ is charged upto $100$ $volt$. The energy stored in the capacitor is........$Joule$

A $2\,\mu F$ capacitor is charged to $100$ $volt$ and then its plates are connected by a conducting wire. The heat produced is........$J$

Two insulated metallic spheres of $3\,\mu F$ and $5\,\mu F$ capacitances are charged to $300\, V$ and $500\,V$ respectively. The energy loss, when they are connected by a wire is

In the figure shown, after the switch $‘S’$ is turned from position $‘A’$ to position $‘B’$, the energy dissipated in the circuit in terms of capacitance $‘C’$ and total charge $‘Q’$ is

A $16\  \Omega$ wire is bend to form a square loop. A $9 \mathrm{~V}$ battery with internal resistance $1\  \Omega$ is connected across one of its sides. If a $4\  \mu \mathrm{F}$ capacitor is connected across one of its diagonals, the energy stored by the capacitor will be $\frac{x}{2} \ \mu \mathrm{J}$. where $x=$________.