If $W$ amount of work is required to increase the voltage of a capacitor from $5\ V$ to $10\ V$,how much work is required to increase the voltage from $10\ V$ to $15\ V$ (in $W$)?

If the energy density in a parallel plate capacitor is given as $1.8 \times 10^{-9} \ J/m^3$,then the value of the electric field in the region between the plates is ....... $NC^{-1}$. (Given: $\epsilon_0 = 9 \times 10^{-12} \ C^2/N \cdot m^2$)

Two capacitors,one of capacity $C$ and the other of capacity $\frac{C}{2}$,are connected to a $V \text{ volt}$ battery,as shown. The work done in charging fully both the capacitors is

The capacity of a capacitor is $4 \times 10^{-6} \, F$ and its potential is $100 \, V$. The energy released on discharging it fully will be ....... $J$.

If the charge on a body is increased by $2 \ C$,the energy stored in it increases by $21 \%$. The original charge on the body in coulomb is:

$A$ parallel plate air capacitor has capacity $C$,distance of separation between plates is $d$,and potential difference $V$ is applied between the plates. The force of attraction between the plates of the parallel plate air capacitor is