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http://www.FreeScienceLectures.com Scientists of the University of Twente in The Netherlands won a prestigious place in the 'Hall of Fame' of videos about fluid-in-motion. They have made a video of leaping shampoo, in which they explain the so-called Kaye effect. A. Kaye in Nature magazine in 1963 wrote "I can offer no explanation for this behaviour." At high-speed recording of 1000 frames per second the following observations were made in 300ms interval: 1) a heap is formed, 2) a streamer ejects, 3) the outgoing jet rises, 4) hits the incoming jet, 5) ends the Kaye effect. What causes the Kaye effect? Streamer ejects through shear-thinning property of fluid. A dimple is formed in the viscous heap. Outgoing jet is thicker quantitatively following continuity. The dimple deepens through a vertical force acting on the viscous heap and the jet rises. The scientists set up a simple energy balance model. It includes viscous dissipation and the sear-thinning behavior of the shampoo in the dimple structure. Elastic properties of the fluid play no role. The model predicts the leap height of the shampoo as a function of the release height. It even predicts a critical release height as observed in experiment. (For details see: JSTAT / 2006 / P07007) To prevent the outgoing jet from interfering with the incoming jet the surface was tilted, leading to a stable Kaye effect cascade. Leaping shampoo may even act as a light guide for laser beams in multitude of colors. The people who worked on this are: Michel Versluis, Cor Blom, Devaraj van Meer, Ko van der Weele, Detlef Lohse. --- It's Never too Late to Study: http://www.FreeScienceLectures.com --- Notice: This video is copyright by its respectful owners. The website address on the video does not mean anything. ---