$A$ $20\,\mu F$ capacitor is charged to a potential of $500\,V$ and then connected in parallel to a $10\,\mu F$ capacitor charged to $200\,V$. What is the common potential in $V$?

Energy of a charged capacitor is $U$. Now it is removed from a battery and then connected to two other identical uncharged capacitors in parallel. What will be the energy of each capacitor?

$A$ capacitor of $4\,\mu F$ charged to $50\,V$ is connected to another capacitor of $2\,\mu F$ charged to $100\,V$ with plates of like charges connected together. The total energy before and after connection in multiples of $10^{-2}\,J$ is:

Two spheres $A$ and $B$ of radii $4 \text{ cm}$ and $6 \text{ cm}$ are given charges of $80 \mu\text{C}$ and $40 \mu\text{C}$ respectively. If they are connected by a fine wire,the amount of charge flowing from one to the other is

$A$ $20 \text{ F}$ capacitor is charged to $5 \text{ V}$ and isolated. It is then connected in parallel with an uncharged $30 \text{ F}$ capacitor. The decrease in the energy of the system will be: (in $\text{ J}$)

Two spheres $A$ and $B$ of radius $4\,cm$ and $6\,cm$ are given charges of $80\,\mu C$ and $40\,\mu C$ respectively. If they are connected by a fine wire,the amount of charge flowing from one to the other is