The essence of siphon is caused by liquid pressure and atmospheric pressure. Because h 1
In addition, there are atmospheric pressures at point B and point C respectively, and the atmospheric pressures are high or low, but from the calculation height of the earth's atmospheric pressure, the atmospheric pressure difference between point B and point C can be ignored.
Therefore, p1-rhogh1>; P2-ρgh2, then the pressure at the left end of A is greater than the pressure at the right end of A, and under the joint action of atmospheric pressure and liquid pressure, water moves in one direction.
Extended data:
Because the air pressure on both sides is basically the same, the depth of the high-level nozzle entering the liquid level is much lower than that of the low-level nozzle, so the pressure at the low-level nozzle is greater than that at the high-level nozzle, but the liquid will still flow from the high-level container into the low-level container.
This phenomenon occurs because the pressure here can only be transferred to the upper surface of the liquid. Therefore, although the pipe pressure in the lower cup is high, it can't be transmitted to the higher cup, so it can't stop the liquid from falling.
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