What is surface tension?

Surface tension is defined as the force required to break the surface of a liquid. This phenomenon arises due to the cohesive forces between liquid molecules, particularly at the surface. In a liquid, molecules experience attractive forces from all directions, but those on the surface are acted upon by molecules in the liquid below them, creating a net inward force. This results in the surface behaving like a stretched elastic membrane.

Understanding surface tension is crucial in various biological processes, such as the ability of small insects to walk on water and the formation of droplets. The higher the cohesive forces among molecules, the greater the surface tension. This property significantly influences phenomena in both biology and physics, illustrating the importance of molecular interactions in determining physical characteristics of substances.