Abstract :
Any vector component of the magnetizing force at a point in space due to an electric current is directly related to a vector representing the surface swept over by the radius vector of length 1/¿r with its origin and direction the same as those of the radius vector r directed from the point in question to consecutive points on the path of the influencing current. This relationship enables magnetizing force, distribution of the magnetic field, electromagnetic forces, etc., to be calculated by means of simple geometry in all practical cases, including those in which no simple analysis has so far been possible.