Ampere, the SI unit of electric current, is defined as the electromagnetice force per unit length between two wires of infinite length, having negligible diameter and placed 1 m apart in vacuum.

Is magnetic force constant?

The magnetic constant μ₀ (also known as vacuum permeability or permeability of free space) is a universal physical constant, relating mechanical and electromagnetic units of measurement.

Is ampere a law?

Ampere's law states that “The magnetic field created by an electric current is proportional to the size of that electric current with a constant of proportionality equal to the permeability of free space.”