kapillärfringen

Kapillärfringen is a term that describes the phenomenon of liquid rising or being drawn up into narrow spaces, known as capillaries. This occurs due to the interplay of adhesive and cohesive forces. Adhesion refers to the attraction between the liquid molecules and the surface of the capillary, while cohesion is the attraction between the liquid molecules themselves.

When the adhesive forces between the liquid and the capillary walls are stronger than the cohesive forces within the liquid, the liquid will "wet" the surface and be pulled upwards. This upward movement continues until the weight of the liquid column balances the capillary forces. The narrower the capillary tube, the higher the liquid will rise.

This principle is fundamental to many natural and technological processes. In plants, capillary action allows water and nutrients to be transported from the roots to the leaves, defying gravity. In everyday life, it can be observed when a paper towel absorbs spilled liquid or when ink spreads on blotting paper. Industrially, capillary action is utilized in technologies like inkjet printing and in the wicking of liquids in certain filtration systems. The extent of capillary rise can be predicted by the Jurin's Law, which relates the height of the liquid column to the surface tension of the liquid, the contact angle between the liquid and the capillary wall, the radius of the capillary, and the acceleration due to gravity.