Three point charges are placed at the corners of an equilateral triangle of side $L$ as shown in the figure.

As shown in the figure, a point charge $q_{1} = +1 \times 10^{-8} \ C$ is placed at the origin in the $x-y$ plane and another point charge $q_{2} = +3 \times 10^{-6} \ C$ is placed at the coordinate $(10, 0)$. In that case, which of the following graph$(s)$ shows most correctly the electric field vector $E_{x}$ in the $x$-direction?

Two point charges $+q$ and $-q$ are held fixed at $(-d, 0)$ and $(d, 0)$ respectively of a $(X, Y)$ coordinate system. Then:

Six point charges are placed at the vertices of a regular hexagon of side $a$ as shown. If $E$ represents the electric field and $V$ represents the electric potential at the center $O$,then:

Four electric charges $+Q, -Q, +Q$,and $-Q$ are placed at the four corners of a square. What are the electric field $(E)$ and electric potential $(V)$ at the center of the square?

Two electric charges $+2 \mu C$ and $-4 \mu C$ are separated by a distance $3 \ m$ in air. At a point $P$ located on the line joining the two charges and in between them, the electric potential is zero. Then the electric field at point $P$ (in $NC^{-1}$) is (in $,000$)