This core principle of physics dictates that multiplying the magnitudes of two electric charges yields a value that scales directly with the electrostatic force between them, while this force diminishes as the distance separating the charges gets squared. It explains why high-voltage clearance requirements must increase exponentially, rather than linearly, to prevent arcing across air gaps.
Heard on the job
Coulomb's law dictates that doubling the distance between those live busbars drops the attractive force to a quarter.