Abstract :
Formulas are presented and derived, which have not been previously published, for mutual inductance of coils with parallel axes, repulsion of coils with parallel axes, and self-inductance of long cylindrical coils. These formulas apply to practically all cases of reactance coils in common use. They are very convergent and accurate, and will give results to a given degree of accuracy with a minimum amount of labor. For many engineering problems, precise accuracy is not required, and sets of curves are given from which approximate readings may be taken.
