
$C_{2}=\frac{\varepsilon_{0} K_{2} \frac{L^{2}}{2}}{\frac{d}{2}}+\frac{\varepsilon_{0} K_{4} \frac{L^{2}}{2}}{\frac{d}{2}}=\frac{\varepsilon_{0} L^{2}}{d}\left(K_{2}+K_{4}\right)$
$\therefore \quad \frac{1}{c}=\frac{1}{c_{1}}+\frac{1}{c_{2}}$
$\Rightarrow \quad \frac{\mathrm{d}}{\varepsilon_{0} \mathrm{KL}^{2}}=\frac{\mathrm{d}}{\varepsilon_{0} \mathrm{L}^{2}\left(\mathrm{K}_{1}+\mathrm{K}_{3}\right)}+\frac{\mathrm{d}}{\varepsilon_{0} \mathrm{L}^{2}\left(\mathrm{K}_{2}+\mathrm{K}_{4}\right)}$
[ $\epsilon_0$ is the permittivity of free space]
$(A)$ $\frac{E_1}{E_2}=1$ $(B)$ $\frac{E_1}{E_2}=\frac{1}{K}$ $(C)$ $\frac{Q_1}{Q_2}=\frac{3}{K}$ $(D)$ $\frac{ C }{ C _1}=\frac{2+ K }{ K }$
