Work done by an external agent in separating the parallel plate capacitor is

If the plates of a parallel plate capacitor connected to a battery are moved close to each other, then

$A$. the charge stored in it, increases.

$B$. the energy stored in it, decreases.

$C$. its capacitance increases.

$D$. the ratio of charge to its potential remains the same.

$E$. the product of charge and voltage increases.

Choose the most appropriate answer from the options given below:

Intially, switch $S$ is connected to position $1$ for a long time shown in figure. The net amount of heat generated in the circuit after it is shifted to position $2$ is 

A charge of $40\,\mu \,C$ is given to a capacitor having capacitance $C = 10\,\mu \,F$. The stored energy in ergs is

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

The insulated spheres of radii ${R_1}$ and ${R_2}$ having charges ${Q_1}$and ${Q_2}$ respectively are connected to each other. There is