What formula represents the electric field at a distance from a point charge?

The formula that represents the electric field at a distance from a point charge is derived from Coulomb's law. It demonstrates how the electric field (E) created by a point charge (q) diminishes with the square of the distance (r) from that charge. The variable k represents Coulomb’s constant, which quantifies the strength of the electrostatic interaction. This relationship shows that as one moves further away from the charge, the strength of the electric field decreases rapidly.

This concept reflects the foundational understanding of how electric fields behave around point charges in electrostatics, adhering to the principle that the intensity of an electric field is inversely proportional to the square of the distance from the source charge. This formulation is critical in various applications, such as calculating forces between charged entities and understanding field lines and potentials in electrostatics.

Other formulas listed pertain to different aspects of electric fields or electric forces. For example, the equation that relates work done (W) to charge (q) expresses electric potential rather than the electric field itself. The formula that involves voltage (V) and distance (d) pertains to the electric field in uniform fields rather than point charges. The last choice includes a term without clear reference to electric field calculations