Science - Capillary Action

- Capillary action is the ability of a liquid to flow against gravity up a narrow tube.  

- It occurs due to the attraction of the liquid surface to the solid surface.  

Examples  

1. Causes the meniscus in a liquid column.  

2. Water can travel up paper.  

3. Water moves upward through a plant stem.  

4. Drawing blood into a capillary tube.  

Forces Involved  

Capillary action is a result of two forces:  

- Cohesive force: Attraction between molecules within the liquid.  

- Adhesive force: Attraction between the liquid and the surface of the tube.  

👉 If adhesive forces are stronger, the liquid will rise in the tube.