When a wire is plucked, it oscillates, generating waves that travel along its length. In this study, we placed a droplet on a stretched wire and observed its behavior during plucking. This phenomenon resembles natural events, such as a guitar string plucked when wet. Using a high-speed camera, we captured the stretching and breakup of the droplet, particularly when the wire moves upward immediately after being plucked.At the initial stage, as the wire moves upward, the attached portion of the water droplet stretches and forms a sheet. A capillary wave emerges on the sheet, enclosed by two rims. As the wire continues its upward motion, the sheet expands vertically and contracts horizontally, eventually leading to the collision of the rims and the formation of a single jet. This jet stretches vertically, detaches from the wire, and breaks into smaller secondary droplets. The breakup is primarily driven by upward inertia and pump-like flow resisted by the downward capillary forces due to the retraction of the droplet.At slower wire speeds, a smoother and more delayed jet breakup occurs. A thicker sheet is formed without capillary waves where capillary retraction forces dominate as the inertia is reduced.We observed different stretching dynamics when using a more viscous fluid, such as a glycerin-water mixture (25 cSt). In this case, the droplet release was delayed, a smoother jet formed, and the jet length increased significantly. No capillary wave patterns were observed on the sheet, as viscous dissipation was sufficient to suppress them. For a shear-thinning viscoelastic fluid with a zero-stress viscosity of around 20 cSt, the jet was even longer, and droplet release was further delayed. This fluid exhibited stronger jet oscillations compared to glycerin, with visible capillary waves on the sheet due to shear-thinning effects.
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