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Someone explained the perfume bottle with the Bernoulli effect: squeezing the bulb over the fluid creates a low pressure area due to the higher speed of the air, which subsequently draws the fluid up. This is illustrated in the following figure.

someone explained

My question is: as shown in the figure, in this pipeline system, because the pipeline at the position of P2 is narrow, the fluid should accelerate, the pressure difference is the cause of acceleration, so the pressure of P1 must be greater than p2, and P2 must be greater than atmospheric pressure (p3), so the high speed can not make the pressure lower than atmospheric pressure, so the liquid level in the vertical pipeline can not be raised.

 can not be raised

My explanation is: The air is viscous, so when air flows horizontally, it will take away the air of the vertical pipe, so the pressure of the vertical pipe decreases, so the liquid level of the vertical pipe will rise. This is illustrated in the following figure.

My explanation

Is my explanation right, or is someone's explanation right?

Reference resources

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    $\begingroup$ Surface tension of the liquid probably account for the vast majority of force required to pull up the column of liquid. It is also the reason why the column of liquid stays in the tube and not empty into the container due to gravity. $\endgroup$ – Melvin Apr 15 at 10:45
  • $\begingroup$ @Melvin Can't the tension be guaranteed to rise so high? $\endgroup$ – enbin zheng Apr 15 at 12:39
  • $\begingroup$ You mean is the surface tension force sufficient to pull the column to that height? It depends on the diameter of the tube and the inner surface of the tube, but in the case of perfume bottles it almost certainly can. $\endgroup$ – Melvin Apr 17 at 1:46
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    $\begingroup$ I think its the pressure difference created by fast moving air particles. And not surface tension. Because if it is surface tension then when we stop using this gadget the liquid level falls or else liquid leaks out. $\endgroup$ – Naga Sandesh Goli Jul 3 at 7:57
  • $\begingroup$ @Melvin I mean, the viscosity of air causes the air to be taken away, so that the pressure is lowered and the liquid level rises. $\endgroup$ – enbin zheng Jul 3 at 8:24

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