An LC circuit is just an inductor (L) and a capacitor (C) connected together. It's the electrical equivalent of a mass on a spring: the inductor stores energy in a magnetic field (like a spring stores energy when compressed), and the capacitor stores energy in an electric field (like the mass stores kinetic energy when moving).
When you "pluck" an LC circuit — give it a brief pulse of energy — the energy bounces back and forth between the inductor and the capacitor at the circuit's natural resonant frequency:
f = 1 / (2π√(LC))
This is the foundational equation of resonance. A bigger inductor or bigger capacitor = lower resonant frequency. A smaller inductor or smaller capacitor = higher resonant frequency.
Why it matters
Every Open Energy experiment that involves resonance is ultimately an LC circuit — sometimes with the L and C as discrete components, sometimes with them built into the geometry of the device itself (like a coil's parasitic capacitance creating a "free" C alongside its intended L).
Understanding LC circuits is the key to understanding why self-resonant frequency changes with winding geometry, why Q factor matters, and why the meta-pattern keeps appearing in the patent literature.