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
$\frac{C}{2}\left( {{\varepsilon _1} + {\varepsilon _2}} \right){\varepsilon _2}$
$C\left( {{\varepsilon _1} + {\varepsilon _2}} \right){\varepsilon _2}$
$\frac{C}{2}{\left( {{\varepsilon _1} + {\varepsilon _2}} \right)^2}$
$C{\left( {{\varepsilon _1} + {\varepsilon _2}} \right)^2}$
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:
A $2\,\mu F$ capacitor is charged to $100$ $volt$ and then its plates are connected by a conducting wire. The heat produced is........$J$
A variable condenser is permanently connected to a $100$ $V$ battery. If the capacity is changed from $2\,\mu \,F$ to $10\,\mu \,F$, then change in energy is equal to
A body of capacity $4\,\mu \,F$ is charged to $80\,V$ and another body of capacity $6\,\mu \,F$ is charged to $30\,V$. When they are connected the energy lost by $4\,\mu \,F$ capacitor is.......$mJ$
Three capacitors of capacitances $25 \mu \mathrm{F}, 30 \mu \mathrm{F}$ and $45 \mu \mathrm{F}$ are connected in parallel to a supply of $100$
$V$. Energy stored in the above combination is $\mathrm{E}$. When these capacitors are connected in series to the same supply, the stored energy is $\frac{9}{\mathrm{x}} \mathrm{E}$. The value of $x$ is___________.