Final answer:
Porous building materials utilize capillary action to wick water, a process driven by adhesive and cohesive forces that allows liquids to move against gravity. This mechanism is also employed in natural processes, such as water transport in plants, and in everyday items like towels.
Step-by-step explanation:
Porous building materials are capable of wicking water for large distances due to capillary action. This phenomenon occurs when a liquid flows within a porous material because of the attraction of the liquid molecules to the surface of the material and to other liquid molecules. Adhesive forces between the liquid and the porous substance, along with the cohesive forces within the liquid, enable the movement of the liquid upward against the pull of gravity.
Capillary action is evident in everyday life, such as when a paper towel absorbs spilled wine, or a cotton towel dries your skin after a shower. This is because fibers in materials like cotton form small capillary tubes that have good adhesion with water. In nature, capillary action is significant as it assists in transporting water from the roots to the tops of trees, demonstrating its vital role in plant hydration.