Surface tension effects of surface tension can be seen with ordinary water: Surface tension is visible in other common phenomena, especially when surfactants are used to decrease it: Surface tension, represented by the symbol "γ" (alternatively "σ" or "T"), is measured in force per unit length. Its SI unit is newton per meter but the cgs unit of dyne per centimeter is also used. For example, Surface tension can be defined in terms of force or energy. In terms of force: surface tension of a liquid is the force per unit length. In the illustration on the right, the rectangular frame, composed
Surface tension term surface energy, which is a more general term in the sense that it applies also to solids. In materials science, surface tension is used for either surface stress or surface energy. Due to the cohesive forces a molecule is pulled equally in every direction by neighboring liquid molecules, resulting in a net force of zero. The molecules at the surface do not have the "same" molecules on all sides of them and therefore are pulled inward. This creates some internal pressure and forces liquid surfaces to contract to the minimal area. The forces of attraction acting between the molecules