Abstract: The vector magnetic potential of a system consisting a line electric current and an infinite long magnetic dielectric column is calculated with the method of separation of variables and method of images, it is pionted out that the vector magnetic potential of a system consisting a line electric current and a magnetic dielectric plane, an ideal paramagnetic column, a superconductor column, and a line electric current in homogeneous magnetic field can all be deduced from our calculation.

Key words: line electric current, magnetic dielectric column, vector magnetic potential, the limit conditions