kapillárískra

Kapillárískra is an Icelandic word that translates to "capillary action" in English. It refers to the ability of a liquid to flow in narrow spaces without the assistance of, or even in opposition to, external forces like gravity. This phenomenon is observed in narrow tubes, porous materials, and even within biological systems.

The underlying principle of capillary action is the interplay between adhesive forces and cohesive forces. Adhesive forces are the attractive forces between the liquid molecules and the molecules of the surrounding surface. Cohesive forces are the attractive forces between the liquid molecules themselves. When the adhesive forces between the liquid and the surface are stronger than the cohesive forces within the liquid, the liquid will tend to climb up the surface. Conversely, if cohesive forces are stronger, the liquid may form a meniscus that curves downwards.

Common examples of capillary action include water moving up the xylem vessels in plants, allowing them to transport water from the roots to the leaves. It's also responsible for ink being drawn into the tip of a pen, the way water is absorbed by a paper towel, and how oil rises in a lamp wick. The narrowness of the space, or capillary, is crucial for this effect to be noticeable. The narrower the tube or pore, the higher the liquid will rise or spread.