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Core ConceptsMeta-pattern elementBeginner

Resonance

When a system is driven at its natural frequency, energy builds up instead of dissipating.

Resonance happens when you push something at exactly the rhythm it naturally wants to move. Push a swing at the wrong time and you fight it. Push at the right time and the swing goes higher with each push — even though you're not pushing harder.

Electrical circuits do the same thing. Every circuit that has both inductance (a coil) and capacitance (a capacitor) has a natural frequency where energy sloshes back and forth between the magnetic field and the electric field. At that frequency, a small input produces a large response.

Why it matters for Open Energy

Resonance is one of the three elements of the meta-pattern found across 768 energy patents. 389 of those patents explicitly describe a resonance condition — making it the single most common design element in the dataset.

The hypothesis is that resonance allows energy to accumulate in a system rather than dissipating, and when combined with non-linearity and pulsed excitation, the system may exhibit behaviors that conventional steady-state analysis doesn't predict.

Everyday examples

  • A wine glass shattering when a singer hits the right note
  • A bridge swaying dangerously when soldiers march in step (which is why soldiers break step on bridges)
  • A microwave oven heating food at 2.45 GHz — the resonant frequency of water molecules
  • Tuning a radio to a station — you're adjusting an LC circuit to resonate at the broadcast frequency

In the experiments

The Bifilar Coil Resonance Characterization experiment directly measures resonance by sweeping a frequency range and finding where a coil's impedance peaks. The Electrolytic Cell Resonance experiment does the same thing with a water cell instead of a coil.

Going deeper

  • Self-Resonant Frequency — the specific frequency where a component resonates due to its own parasitic properties
  • Q Factor — how "sharp" the resonance is (high Q = energy stays in the system longer)
  • LC Circuit — the simplest resonant circuit: one inductor + one capacitor