Equations · equation
Capillary Rise
Fluid Dynamics · 1718
- Equation
- h = 2 γ cos θ / (ρ g r)
- Field
- Fluid Dynamics
- Named After
- James Jurin
- Year
- 1718
Symbols
h height the liquid climbs in a narrow tube · γ surface tension · θ contact angle between liquid and wall · ρ liquid density · g gravitational acceleration · r tube radius
Significance
Liquid climbs a narrow gap when it wets the walls, and higher the narrower the gap — Jurin's law of 1718. It draws molten solder and brazing alloy into a joint that fits closely and refuses one that does not, lifts water through soil and up a plant, and wicks ink into paper. When the liquid does not wet, θ passes 90° and it is pushed out instead: mercury in glass.
Referenced by
equation
skill
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