"Benevolence benefits, full moves" -The principle of magical suction in the Kowloon Cup

The emperor Zhu Yuanzhang of the Ming Dynasty invited the founding heroes one day. During the meeting, he took out a porcelain wine glass and said to everyone: "You follow me in the south to fight and north. Come and drink for a cup! "After that, Xu Da first stepped forward to receive the reward. As soon as Xu Da came to the greedy cup, the two came from the high merit, so he poured the wine in the cup. Who knew that when he got up the wine glass, the wine in the cup leaked. As long as others do not fill the wine, they can drink it at once, and everyone is puzzled. Zhu Yuanzhang laughed and said, "The so -called‘ full move, humility benefit ’! Hahahaha.”

This magical cup is called the "Kowloon Fair Cup". Once the wine is filled, the wine will leak the light along the dragon head in the middle. The principle is the "siphon principle" we are talking about today.

If you want to figure out what is the principle of rainbow suction, you must first understand how the pressure in the liquid is calculated, and how the pressure is passed in the liquid, to see a simple example:

This is a container containing water. Assuming the atmospheric pressure is P0, calculate the pressure of A, B, and C along the path shown by the red arrow in the figure.

It can be seen from the liquid pressure formula, the pressure of point A

Point B and point A are at the same level, so

C is above B, hence

You can also write here,

But in order to explain the problem, we use the previous writing, that is,

It can be seen that the transmission of the pressure in the liquid along a certain road depends on the horizontal location of the research object. This is why the diver feels the water pressure in the deep water area and it is difficult to breathe.

With the above foundation, let's take a look at a classic rainbow original picture:

As shown in the figure, there are two water cups placed on different levels, one is equipped with water, and the other is empty. The two are connected by a U -shaped tube that is not equal to both sides. To the bottom of the water cup, the other side is facing the empty water cup.

Use your mouth to suck the water from the U -shaped tube a little, so that the U -shaped tube is filled with water and reaches the position of the figure below:

At the highest point of the U -shaped tube, compare the pressure on the left and right sides

According to the first example, we can know

The pressure on the left side is passed to it by the water in the left water cup

Therefore

Similarly, the pressure on the right is

Obviously, h P> P

The water on the left side of the U -shaped tube will continue to be automatically sucked to the right, and the magical phenomenon of water flowing to high places will appear.

It should be noted that if you want to suck the water in the left cup clean, you need to ensure that the height of the liquid surface in the right cup does not exceed the height of the left side of the U -shaped tube, that is, the h> 0 in the figure below.

After understanding the basic principle of siphon phenomenon,

Back to the beginning of the Kowloon Fair Cup

Its structure is probably like this:

It seems that Xu Da is not wronged at all!

Humidity is a virtue ~

In addition to the Jiulong fair cup mentioned here, the principle of siphon can often be seen in our daily life. For example, the siphon -type dumping toilet can greatly increase the sewage efficiency and reduce the blockage.

Can you see its working principle at a glance?

Another example can be used for changing the fish tank,

Save a spoonful of effort to the water out of water ~

It can be seen that the seemingly simple siphon effect is often used cleverly in life. With it, you can test the character and allow the water to flow to the high place. Water ... really wonderful! Intersection Intersection Intersection

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Source: science science

Edit: lychee jelly

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