What is the principle of communicating devices? What if the rubber tube is used as a connecting device to change the water for the fish?
Siphon principle: that is the principle of connected devices, plus in a closed container, the pressure on the liquid, everywhere equal. The siphon is filled with water, there is no gas, the water level of the water inlet is high, and the water outlet is closed with palm or other objects. The pressure is equal everywhere. When all are arranged, the water outlet is opened, although the atmospheric pressure on both sides is equal, the water level at the water inlet end is high and the pressure is large, and the water inflow is continuously flowed out of the water outlet.
The principle of communicating devices can be explained by liquid pressure. If the same liquid is contained in a U glass tube, a small liquid AB is conceived at the center of the bottom of the communicating device. If the liquid is stationary, it does not flow. The pressure of the liquid in the left tube toward the right side of the liquid AB must be equal to the pressure of the liquid in the right tube toward the left of the liquid AB. Because in the communicating vessel is filled with a liquid, the same two liquid column density, according to the formula of P= P GH liquid pressure that only when both sides is equal to the height of liquid column, the liquid column is equal to the pressure on both sides of the liquid film AB. Therefore, in the case of no flow of liquid, the liquid level in each vessel of the communicating device shall be kept flat. (ideal model method) the connecting device is characterized in that the liquid level in each container is flat only when the same liquid is contained in the container. If the container is tilted, the liquid in each container is about to begin to flow. One end of the liquid column flows to the lower end of the liquid column and stops flowing until the liquid level in each container is normal. As with rubber tube two glass tubes connected together in container with a liquid, which will be a fixed tube, the other tube up and down or tilt, can see the two tube level in stationary phase remained flat. The connecting device is provided with the same liquid, but the pressure on the liquid surface is unequal, and the pressure difference of the liquid surface is equal to the pressure difference produced by the liquid level difference of the two container of the communicating device.
The principle of siphon principle has long been known by the Chinese people for the discovery and application of siphon principle. Hong Straw manufacturing principle application of siphon, in ancient China called "sub", "partial" and "siphon" or "siphon". At the end of the Eastern Han Dynasty, thirsty for irrigation appeared. In southwest minority with a long curved bamboo festival to drink, but also the application of the physical phenomenon of siphon. The song "Ceng Gongliang Wujing Zongyao", making the Straw useful bamboo rainbow mountains spring bring down the record barrier. China ancient also uses siphon principle is made. A fire extinguisher is a necessary war in the city. The Song Dynasty Su Shi "dongpozhilin" Volume 4, recorded by the Sichuan salt brine pump suction to the ground. The book contains: the bamboo tube, no bottom orifices on the leather hanging a few inches out of the water, gas, breathing and the opening and closing of a cylinder caused by water bucket number. "Using the method of pump water to irrigate seedlings induced in the Ming Dynasty also talked about the" tree "in the book, the ancient China siphon principle is also discussed. During the northern and Southern Dynasties, the book "Yin Zi nine drugs", said: "the bottle stored two orifices, the water to the reality of the" pour "; closed a water, the lid (gas) does not rise, then (water) does not drop. A well is full of water, but it does not drop
