Young's equation

Young's equation

The Young's equation (by Thomas Young ) illustrates a relationship between ago

• the free specific surface energy σ _{SG of} a flat solid body (index _SG for solid gas ) to the surrounding gas
• the specific surface energy σ _LS between the solid and a thereon liquid drop (index _LS for engl. liquid-solid )
• the surface tension σ _{LG of} the liquid (index _LG for liquid gas ) to the surrounding gas
• the contact angle Θ between the two.

It is:

${\displaystyle \cos \Theta ={\frac {\sigma _{SG}-\sigma _{LS}}{\sigma _{LG}}}}$

In 1869 , the French physicist Athanase Dupré first described a quantitative relationship between the forces occurring at the phase boundary of a solid and a liquid substance.

Individual evidence

1. ^ Young, Thomas: An Essay on the Cohesion of Fluids . Philosophical Transactions of the Royal Society of London, The Royal Society, London 1805, Vol. 95, pp. 65--87 ( full text )
2. ↑ Claus Bischof, Wulff Possart: Adhesion - Theoretical and experimental foundations . Akademie-Verlag, Berlin 1983, p. 17 and p. 28

Web links

• Video: YOUNG contact angle and capillarity - how high does water rise in a capillary? . Jakob Günter Lauth (SciFox) 2013, made available by the Technical Information Library (TIB), doi : 10.5446 / 15673 .