MiS Preprint Repository

We have decided to discontinue the publication of preprints on our preprint server as of 1 March 2024. The publication culture within mathematics has changed so much due to the rise of repositories such as ArXiV ( that we are encouraging all institute members to make their preprints available there. An institute's repository in its previous form is, therefore, unnecessary. The preprints published to date will remain available here, but we will not add any new preprints here.

MiS Preprint

The Floating Ball Paradox

Henry C. Wente


In capillary theory there are two kinds of surface tension. There is the surface tension at the interface between two immiscible fluids. Thomas Young (T. Young, An essay on the cohesion of fluids, Phil. Transactions Royal Society, London, 95, (1805) 65-87) also allowed for there to be a surface tension associated with a liquid-solid interface. He proceeded to use a balance of forces argument to derive the well-known contact angle condition along a liquid-liquid-solid intersection. The validity of this argument has recently been called into question by R. Finn (R. Finn, The contact angle in capillarity, Physics of Fluids 18, 047102, (2006)). A floating ball experiment discussed in that paper leads to an apparent paradox. We address this issue.

Please see also the MPI MIS preprint 154/2006 by Robert Finn.

MSC Codes:
76B45, 76D45, 74G65
capillarity, surface tension

Related publications

2008 Repository Open Access
Henry C. Wente

The floating ball paradox

In: Journal of mathematical fluid mechanics, 10 (2008) 4, pp. 569-582