The Bernoulli Act. Simple and intelligible

Much of the world around us is subject to the laws of physics. This is not surprising, because the term "physics" comes from the Greek word, in the translation meaning "nature." And one of these laws, constantly working around us, is Bernoulli's law.

By itself, the law is a consequence of the principle of conservation of energy. This interpretation of his interpretation allows us to give a new understanding to many previously well-known phenomena. To understand the essence of the law, it's just enough to remember the flowing trickle. Here it flows, runs between stones, branches and roots. In some places it becomes wider, somewhere already. You can see that where the stream is wider, the water flows more slowly, where already, the water flows faster. This is the Bernoulli principle, which establishes the relationship between the pressure in the fluid flow and the velocity of such a flow.

True, the textbooks of physics formulate it somewhat differently, and he has to do with hydrodynamics, and not a flowing stream. In a rather popular form, the Bernoulli law can be stated in this way: the pressure of the liquid flowing in the pipe is higher where the speed of its movement is less, and vice versa: where the speed is greater, the pressure is less.

To confirm it is enough to conduct a simple experiment. It is necessary to take a sheet of paper and blow along it. The paper rises upwards, in the direction along which the air flow passes.

Everything is very simple. As the Bernoulli law says, where the speed is higher, the pressure is lower. Hence, along the surface of the sheet where the air flow passes , the pressure is lower, and below the sheet, where there is no air flow, the pressure is greater. Here is the sheet and rises to the side where the pressure is less, i.e. Where the flow of air passes.

The described effect is widely used in everyday life and in technology. As an example, you can consider a spray gun or airbrush. They use two tubes, one with a larger cross section, and the other with a smaller one. The one that has a larger diameter is attached to the container with paint, according to the smaller cross section, air passes at a high speed. Due to the resulting difference in pressure, the paint enters the air flow and is transferred by this flow to the surface, which must be colored.

The pump can work on the same principle. In fact, what is described above, and there is a pump.

Equally interesting is Bernoulli's law in the application for draining swamps. As always, everything is very simple. Wetlands are connected by ditches with a river. There is a current in the river, there is no swamp in the swamp. Again, there is a pressure difference, and the river begins to suck the water out of the swampy terrain. There is a pure demonstration of the work of the law of physics.

The impact of this effect can be devastating. For example, if two ships pass close to each other, the speed of water between them will be higher than on the other side. As a result, an additional force will arise, which will attract the ships to each other, and the catastrophe will be inevitable.

It is possible to state all of the above in the form of formulas, but Bernoulli's equations are not necessarily written for understanding the physical essence of this phenomenon.

For a better understanding, we give one more example of using the described law. Everyone imagines a rocket. In a special chamber, the combustion of fuel occurs, and a jet is formed. To accelerate it, a specially narrowed section is used - a nozzle. Here there is an acceleration of the jet of gases and, as a consequence, an increase in jet thrust.

There are still many different options for using the Bernoulli law in engineering, but all of them can not be considered within the framework of this article.

Thus, Bernoulli's law is formulated, an explanation is given of the physical essence of the processes that are taking place, examples from nature and technology show possible options for applying this law.