[link:https://www.livescience.com/why-gas-bubbles-stuck-vertical-tubes.html?utm_source=notification|

By Yasemin Saplakoglu - Staff Writer 2 days ago

A university student recently solved a question that's puzzled physicists for over half a century: Why do gas bubbles appear to get stuck inside narrow vertical tubes? The answer may help explain the behavior of natural gases that are trapped in porous rocks.

Years ago, physicists noticed that gas bubbles in a sufficiently narrow tube filled with liquid did not move. But that's "kind of a paradox," said senior author John Kolinski, an assistant professor in the department of mechanical engineering at the Swiss Federal Institute of Technology Lausanne (EPFL).

That's because the gas bubble is less dense than the liquid surrounding it, so it should rise to the top of the tube (just as air bubbles in a glass of sparkling water will rise to the top). What's more, the only resistance to flow in a liquid comes when that liquid is moving, but in this case the fluid is standing still.

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