Because the water surface of the nozzle bears different atmospheric pressures, the water will flow from the high-pressure side to the low-pressure side until the atmospheric pressures on both sides are equal and the water surface in the container becomes the same height, and the water will stop flowing.

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Siphon engineering application

In 1960s, several Swedish scientists applied siphon principle to modern buildings, and initially solved the rainwater drainage system on the roof of buildings. At that time, in the early stage of research, the whole pipe pressure flow system was adopted, which made a major breakthrough in the rainwater drainage system of pipeline roof. Siphon principle has applications in building drainage, municipal drainage, water conservancy projects and so on.

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