Physics

Kelvin's water dropper

A reduced Kelvin water-dropper circuit amplifies charge through crossed induction. Explore growth, leakage, energy storage and repeated spark discharge powered by falling water.

By Mykhailo Makarov

Actual application image

Try this

Stop the water or open the crossed circuit. The stored charge will leak away.

Equations used in the module

Equations
V1′ = −a V2 − λV1; V2′ = −a V1 − λV2
Differential mode grows at a − λ
E = C(V1² + V2²)/2
Pump power ≤ water gravitational power; sparks dissipate stored energy

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