Dynamics of Droplets on a Plucked Wire: The Role of Wire Speed, Viscosity, and Surface Tension*

When a wire is plucked, it oscillates, creating waves that travel along its length. In this study, we placed a droplet on a stretched wire and observed its behavior upon plucking. This phenomenon is analogous to natural occurrences, such as birds or insects shaking their wings to remove water droplets from their bodies. Using a high-speed camera, we captured the stretching and breakup of the droplet, particularly when the wire moves upward immediately after plucking. Our observations indicate that the stretching of the droplet increases with its viscosity and surface tension but decreases with wire inertia. Additionally, we found that a higher viscosity leads to reduced skewness in the stretched portion of the droplet. This skewness influences the shape, size, and inertia of the smaller droplets formed during breakup. The findings of this study have potential applications in areas such as disease transmission in plants, inkjet printing, and material science.