A physical constant used in electrostatics to calculate the exact force between two point charges in a vacuum. It represents the strength of the electric force in a given system of units and is derived from the permittivity of free space. Engineers rarely use it directly in the field, but it forms the mathematical foundation for calculating capacitance and electric field gradients in high-voltage design.
Heard on the job
You only need Coulomb's constant when you're doing first-principles calculations for the new insulator geometries.