Two pairs of point charges are shown. Pair A consists of charges $q$ and $q$ separated by distance $r$. Pair B consists of charges $q$ and $-q$ separated by the same distance $r$. Which pair experiences an attractive force between the charges?

In a circuit, resistors $R_1$ = $2$ $\Omega$ and $R_2$ = $4$ $\Omega$ are connected in series with a $12$ $V$ battery. What is the magnitude of the current through $R_1$?

Two point charges are separated by a distance of $25.0\mathrm{cm}$. If the charges are $\mathrm{+2.0}\mathrm{\mu C}$ and $-3.0\mathrm{\mu C}$, what is the magnitude of the electrostatic force between them? (Use $k=8.99\times {10}^{9}N·m^2·C^{-2}$)

In the context of electric charge, if all the charges in a figure are point charges, which of the following statements is correct about the electric field at a point not coinciding with any charge?$q$

Four point charges are placed at the corners of a square of side $l$. Each corner has a charge: two adjacent corners have charge $q$ (both positive), and the other two have charge $-q$ (both negative). What is the magnitude of the net electric force on one of the positive charges due to the other three charges?

Two point charges, $q_1$ and $q_2$, are located on the x-axis at positions $x_1$ and $x_2$ respectively. What is the expression for the electric force exerted on $q_1$ by $q_2$?

Consider a rectangular array of identical point charges, each with charge $q$, arranged in a $2\times 3$ grid. If the distance between adjacent charges is $a$, what is the net electric force on the charge located at the center of the array due to the other charges?

If every minute, $120C$ of charge flow through a cross section of a wire, what is the average current in the wire?