Preeti S. Yadav, Prashant Bahadur, Kumud Chaurasia, Aisha Leh, and Rafael Tadmor. Lamar University, Beaumont, TX
The force required to slide a drop past a surface is shown to be a growing function of the time the drop waited on the surface prior to the commencement of sliding along it. In this first report on the “waited time” effect we explore a number of systems and show that this phenomenon is general and takes several minutes before reaching a plateau. Then we use one system to study the phenomenon in greater detail. We provide some semi-quantitative explanation to the experiments.