$A$ regular hexagon with side length '$a$' is shown. Find the electric field and electric potential at point '$A$'.

In the given figure,the charge stored in $6 \ \mu F$ capacitor,when points $A$ and $B$ are joined by a connecting wire is . . . . . . $\mu C$.

In the figure shown below,the charge on the left plate of the $10\, \mu F$ capacitor is $-30\,\mu C.$ The charge on the right plate of the $6\,\mu F$ capacitor is.....$\mu C$.

What is the net force on a small electric dipole placed inside a parallel plate capacitor at steady state,if the plates are separated by $1 \ cm$? The circuit diagram is provided.

Identify the correct statements:
$A$. Effective capacitance of a series combination of capacitors is always smaller than the smallest capacitance of the capacitor in the combination.
$B$. When a dielectric medium is placed between the charged plates of a capacitor,displacement of charges cannot occur due to the insulation property of the dielectric.
$C$. Increasing the area of the capacitor plate or decreasing the thickness of the dielectric is an alternate method to increase the capacitance.
$D$. For a point charge,concentric spherical shells centered at the location of the charge are equipotential surfaces.
Choose the correct answer from the options given below.

$A$ capacitor $A$ has a capacitance of $15\ \mu F$ when filled with a dielectric of constant $K = 15$. Another capacitor $B$ is air-filled and has a capacitance of $1\ \mu F$. Both are charged to $100\ V$. After charging, the dielectric is removed from capacitor $A$, and the two capacitors are connected in parallel. The common potential difference across them will be ... $V$.