Surface Tension and Fluidics

This lecture covers the concept of surface tension, explaining how it arises from the difference in internal adhesion energy of liquids and adhesion energy at interfaces. It discusses the contact angle between liquids and surfaces, the floatability of hydrophobic objects on water, and the behavior of superhydrophobic surfaces. Additionally, it explores electrowetting phenomena, such as modifying contact angles using electrostatic surface energy and creating liquid lenses for applications like autofocus and image stabilization. The lecture also delves into electrocapillary pressure in tubes, electrowetting on dielectrics, and the filling of capillaries using the Washburn equation. Finally, it touches on capillary barriers, strategies to prevent collapse during drying processes, and the fascinating pitch drop experiment.