Daffodil International University

Faculties and Departments => Faculty Sections => Departments => Topic started by: ABM Nazmul Islam on September 30, 2014, 10:09:42 AM

Title: Capillary Action
Post by: ABM Nazmul Islam on September 30, 2014, 10:09:42 AM

Capillary action, or capillarity, is the ability of a liquid to flow in narrow spaces without the assistance of, and in opposition to, external forces like gravity. The effect can be seen in the drawing-up of liquids between the hairs of a paint-brush, in a thin tube, in porous materials such as paper, in some non-porous materials such as liquified carbon fiber, and in a cell. It occurs because of intermolecular attractive forces between the liquid and solid surrounding surfaces. If the diameter of the tube is sufficiently small, then the combination of surface tension (which is caused by cohesion within the liquid) and adhesive forces between the liquid and the container act to lift the liquid.