A parallel plate capacitor has a uniform electric field ' $\overrightarrow{\mathrm{E}}$ ' in the space between the plates. If the distance between the plates is ' $\mathrm{d}$ ' and the area of each plate is ' $A$ ', the energy stored in the capacitor is : $\left(\varepsilon_{0}=\right.$ permittivity of free space)

A $400\, pF$ capacitor is charged with a $100\, V$ battery. After disconnecting battery this capacitor is connected with another $400\, pF$ capacitor. Then find out energy loss.

If the charge on a capacitor is increased by $2C$, the energy stored in it increases by $44 \%$. The original charge on the capacitor is (in $C$ )

A capacitor of capacitance $C$ is charged to potential difference $V_0$. Now this capacitor is connected to an ideal inductor. When $25\%$ of energy of capacitor is transferred to inductor then at that time what will be potential difference across capacitor

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:

The energy required to charge a capacitor of $5\,\mu \,F$ by connecting a $d.c$. source of $20\, kV$ is......$kJ$