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Viscosity from bubble

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Viscosity from bubble diagram
Bubble terminal speed (Hadamard-Rybczynski formula) is inversely proportional to the medium viscosity and proportional to its density. If the system is "dirty" (e.g. with surfactant), then the bubble is further slowed by up to 1/3. Suitable units for inputs and output can be chosen via the menus.
Medium density
Bubble diameter
Distance risen
Time taken

Medium viscosity
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The rising bubble method is a common way of measuring viscosity, although calibrated purpose-designed tubes are used for this purpose. For the case where the bubble is made from a second liquid, or the system is in a centrifuge, one should use the differential density or scale it by the centrifugal force (in units of g).
Remember that this formula is only suitable for small, spherical bubbles in "clean" media.