A reactance theorem

```@article{FosterART,
title={A reactance theorem},
author={Ronald M. Foster},
journal={Bell System Technical Journal},
volume={3},
pages={259-267}
}```
• R. M. Foster
• Published 1 April 1924
• Physics
• Bell System Technical Journal
The theorem gives the most general form of the driving-point impedance of any network composed of a finite number of self-inductances, mutual inductances, and capacities. This impedance is a pure reactance with a number of resonant and anti-resonant frequencies which alternate with each other. Any such impedance may be physically realized (provided resistances can be made negligibly small) by a network consisting of a number of simple resonant circuits (inductance and capacity in series) in…
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