Jet motion in literary works. Jet propulsion in nature and technology - abstract

Jet propulsion in nature and technology - a very common phenomenon. In nature, it occurs when one part of the body separates at a certain speed from some other part. In this case, the reactive force appears without interaction of a given organism with external bodies.

In order to understand what we are talking about, it is best to look at examples. in nature and technology are numerous. We will first talk about how animals use it, and then how it is used in technology.

Jellyfish, dragonfly larvae, plankton and mollusks

Many people, while swimming in the sea, came across jellyfish. In the Black Sea, in any case, there are plenty of them. However, not everyone thought that jellyfish move using jet propulsion. The same method is used by dragonfly larvae, as well as some representatives of marine plankton. The efficiency of invertebrate marine animals that use it is often much higher than that of technical inventions.

Many mollusks move in a way that interests us. Examples include cuttlefish, squid, and octopus. In particular, the scallop clam is able to move forward using a jet of water that is ejected from the shell when its valves are sharply compressed.

And these are just a few examples from the life of the animal world that can be cited to expand on the topic: “Jet propulsion in everyday life, nature and technology.”

How does a cuttlefish move?

The cuttlefish is also very interesting in this regard. Like many cephalopods, it moves in water using the following mechanism. Through a special funnel located in front of the body, as well as through a side slit, the cuttlefish takes water into its gill cavity. Then she vigorously throws it through the funnel. The cuttlefish directs the funnel tube back or to the side. The movement can be carried out in different sides.

The method that the salpa uses

The method that the salpa uses is also curious. This is the name of a sea animal that has a transparent body. When moving, the salpa draws in water using the front opening. The water ends up in a wide cavity, and gills are located diagonally inside it. The hole closes when the salpa takes a large sip of water. Its transverse and longitudinal muscles contract, compressing the entire body of the animal. Water is pushed out through the rear hole. The animal moves forward due to the reaction of the flowing jet.

Squids - "living torpedoes"

The greatest interest is, perhaps, the jet engine that the squid has. This animal is considered the largest representative of invertebrates, living at great ocean depths. Squids have achieved true perfection in jet navigation. Even the body of these animals resembles a rocket with its external forms. Or rather, this rocket copies the squid, since it is the squid that has the undisputed primacy in this matter. If it needs to move slowly, the animal uses a large diamond-shaped fin for this, which bends from time to time. If a quick throw is needed, a jet engine comes to the rescue.

The mollusk's body is surrounded on all sides by a mantle - muscle tissue. Almost half of the total volume of the animal’s body is the volume of its cavity. The squid uses the mantle cavity to move by sucking water inside it. Then he sharply throws out the collected stream of water through a narrow nozzle. As a result of this, it pushes backwards at high speed. At the same time, the squid folds all 10 tentacles into a knot above its head in order to acquire a streamlined shape. The nozzle contains a special valve, and the animal's muscles can turn it. Thus, the direction of movement changes.

Impressive squid speed

It must be said that the squid engine is very economical. The speed that it is capable of reaching can reach 60-70 km/h. Some researchers even believe that it can reach up to 150 km/h. As you can see, the squid is not called the “living torpedo” for nothing. It can turn in the desired direction, bending its tentacles folded in a bundle down, up, left or right.

How does a squid control movement?

Since the steering wheel is very large compared to the size of the animal itself, only a slight movement of the steering wheel is sufficient for the squid to easily avoid a collision with an obstacle, even moving at maximum speed. If you turn it sharply, the animal will immediately rush into reverse side. The squid bends the end of the funnel back and, as a result, can slide head first. If he bends it to the right, he will be thrown to the left by the jet thrust. However, when it is necessary to swim quickly, the funnel is always located directly between the tentacles. In this case, the animal rushes tail first, like the running of a fast-moving crayfish if it had the agility of a racer.

When there is no need to rush, cuttlefish and squid swim, undulating with their fins. Miniature waves run across them from front to back. Squid and cuttlefish glide gracefully. They only push themselves from time to time with a stream of water that shoots out from under their mantle. The individual shocks that the mollusk receives during the eruption of jets of water are clearly visible at such moments.

Flying squid

Some cephalopods are capable of accelerating up to 55 km/h. It seems that no one has made direct measurements, but we can give such a figure based on the range and speed of flying squids. It turns out that there are such people. The Stenoteuthis squid is the best pilot of all mollusks. English sailors call it a flying squid (flying squid). This animal, the photo of which is presented above, has Not large sizes, about the size of a herring. It chases fish so quickly that it often jumps out of the water, skimming like an arrow over its surface. He also uses this trick when he is in danger from predators - mackerel and tuna. Having developed maximum jet thrust in the water, the squid launches into the air and then flies more than 50 meters above the waves. When it flies, it is so high that frequent flying squids end up on the decks of ships. A height of 4-5 meters is by no means a record for them. Sometimes flying squids fly even higher.

Dr. Rees, a mollusk researcher from Great Britain, in his scientific article described a representative of these animals, whose body length was only 16 cm. However, he was able to fly a fair distance through the air, after which he landed on the bridge of a yacht. And the height of this bridge was almost 7 meters!

There are times when a ship is attacked by many flying squids at once. Trebius Niger, an ancient writer, once told a sad story about a ship that seemed unable to withstand the weight of these sea animals and sank. Interestingly, squids are able to take off even without acceleration.

Flying octopuses

Octopuses also have the ability to fly. Jean Verany, a French naturalist, watched one of them speed up in his aquarium and then suddenly jump out of the water. The animal described an arc of about 5 meters in the air and then plopped down into the aquarium. The octopus, gaining the speed necessary for the jump, moved not only thanks to jet thrust. It also paddled with its tentacles. Octopuses are baggy, so they swim worse than squids, but at critical moments these animals can give a head start to the best sprinters. California Aquarium workers wanted to take a photo of an octopus attacking a crab. However, the octopus, rushing at its prey, developed such a speed that the photographs, even when using a special mode, turned out to be blurred. This means that the throw lasted only a fraction of a second!

However, octopuses usually swim quite slowly. Scientist Joseph Seinl, who studied the migrations of octopuses, found that the octopus, whose size is 0.5 m, swims at an average speed of about 15 km/h. Each jet of water that he throws out of the funnel propels him forward (more precisely, backward, since he swims backwards) by about 2-2.5 m.

"Squirting cucumber"

Reactive movement in nature and technology can be considered using examples from the plant world to illustrate it. One of the most famous is the ripened fruits of the so-called They bounce off the stalk at the slightest touch. Then, from the resulting hole, a special sticky liquid containing the seeds is ejected with great force. The cucumber itself flies in the opposite direction at a distance of up to 12 m.

Law of conservation of momentum

You should definitely talk about it when considering jet motion in nature and technology. Knowledge of the law of conservation of momentum allows us to change, in particular, our own speed of movement if we are in open space. For example, you are sitting in a boat and you have several stones with you. If you throw them in a certain direction, the boat will move in the opposite direction. IN outer space This law also applies. However, for this purpose they use

What other examples of jet propulsion can be noted in nature and technology? Very well illustrated with the example of a gun.

As you know, a shot from it is always accompanied by recoil. Let's say the weight of the bullet was equal to the weight of the gun. In this case, they would fly apart at the same speed. Recoil occurs because a reactive force is created, since there is a thrown mass. Thanks to this force, movement is ensured both in vacuum and in air. The greater the speed and mass of the flowing gases, the greater the recoil force that our shoulder feels. Accordingly, the stronger the reaction of the gun, the higher the reaction force.

Dreams of flying into space

Jet propulsion in nature and technology has already for many years is a source of new ideas for scientists. For many centuries, humanity has dreamed of flying into space. The use of jet propulsion in nature and technology, it must be assumed, has by no means exhausted itself.

And it all started with a dream. Science fiction writers several centuries ago offered us various means of how to achieve this desired goal. In the 17th century, Cyrano de Bergerac, a French writer, created a story about a flight to the moon. His hero reached the Earth's satellite using an iron cart. Over this structure he constantly threw strong magnet. The carriage, attracted to him, rose higher and higher above the Earth. Eventually she reached the moon. Another famous character, Baron Munchausen, climbed to the moon using a bean stalk.

Of course, at that time little was known about how the use of jet propulsion in nature and technology could make life easier. But the flight of fancy certainly opened up new horizons.

On the way to an outstanding discovery

In China at the end of the 1st millennium AD. e. invented jet propulsion to power rockets. The latter were simply bamboo tubes that were filled with gunpowder. These rockets were launched for fun. The jet engine was used in one of the first automobile designs. This idea belonged to Newton.

N.I. also thought about how jet motion arises in nature and technology. Kibalchich. This is a Russian revolutionary, the author of the first project of a jet aircraft, which is intended for human flight. The revolutionary, unfortunately, was executed on April 3, 1881. Kibalchich was accused of participating in the assassination attempt on Alexander II. Already in prison, while awaiting execution of the death sentence, he continued to study such interesting phenomenon, as a reactive movement in nature and technology that occurs when part of an object is separated. As a result of these researches, he developed his project. Kibalchich wrote that this idea supports him in his position. He is ready to calmly face his death, knowing that such an important discovery will not die with him.

Realization of the idea of ​​space flight

The manifestation of jet propulsion in nature and technology continued to be studied by K. E. Tsiolkovsky (his photo is presented above). At the beginning of the 20th century, this great Russian scientist proposed the idea of ​​​​using rockets for space flights. His article on this issue appeared in 1903. It presented a mathematical equation that became the most important for astronautics. It is known in our time as the “Tsiolkovsky formula”. This equation described the motion of a body having variable mass. In his further works, he presented a diagram rocket engine, running on liquid fuel. Tsiolkovsky, studying the use of jet propulsion in nature and technology, developed a multi-stage rocket design. He also came up with the idea of ​​​​the possibility of creating entire space cities in low-Earth orbit. These are the discoveries the scientist came to while studying jet propulsion in nature and technology. Rockets, as Tsiolkovsky showed, are the only devices that can overcome a rocket. He defined it as a mechanism with a jet engine that uses the fuel and oxidizer located on it. This device transforms the chemical energy of the fuel, which becomes the kinetic energy of the gas jet. The rocket itself begins to move in the opposite direction.

Finally, scientists, having studied the reactive movement of bodies in nature and technology, moved on to practice. A large-scale task lay ahead to realize the long-standing dream of humanity. And a group of Soviet scientists, led by Academician S.P. Korolev, coped with it. She realized Tsiolkovsky's idea. First artificial satellite of our planet was launched in the USSR on October 4, 1957. Naturally, a rocket was used.

Yu. A. Gagarin (pictured above) was the man who had the honor of being the first to fly in outer space. This important event for the world took place on April 12, 1961. Gagarin flew around the entire globe on the Vostok satellite. The USSR was the first state whose rockets reached the Moon, flew around it and photographed the side invisible from Earth. In addition, it was the Russians who visited Venus for the first time. They brought scientific instruments to the surface of this planet. American astronaut Neil Armstrong is the first person to walk on the surface of the Moon. He landed on it on July 20, 1969. In 1986, Vega 1 and Vega 2 (ships belonging to the USSR) explored at close range Halley's Comet, which approaches the Sun only once every 76 years. Space exploration continues...

As you can see, physics is a very important and useful science. Jet propulsion in nature and technology is just one of interesting questions which are discussed in it. And the achievements of this science are very, very significant.

How jet propulsion is used in nature and technology these days

In physics, particularly important discoveries have been made in the last few centuries. While nature remains virtually unchanged, technology is developing at a rapid pace. Nowadays, the principle of jet propulsion is widely used not only by various animals and plants, but also in astronautics and aviation. In outer space there is no medium that a body could use to interact in order to change the magnitude and direction of its speed. That is why only rockets can be used to fly in airless space.

Today, jet propulsion is actively used in everyday life, nature and technology. It is no longer a mystery as it used to be. However, humanity should not stop there. New horizons are ahead. I would like to believe that the jet movement in nature and technology, briefly described in the article, will inspire someone to make new discoveries.

For most people, the term "jet propulsion" is represented as modern progress in science and technology, especially in the field of physics. Jet propulsion in technology is associated by many with spaceships, satellites and jet aircraft. It turns out that the phenomenon of jet propulsion existed much earlier than man himself, and independently of him. People have only managed to understand, use and develop what is subject to the laws of nature and the universe.

What is jet propulsion?

On English the word "reactive" sounds like "jet". It refers to the movement of a body, which is formed in the process of separating a part from it at a certain speed. A force appears that moves the body in the opposite direction from the direction of movement, separating a part from it. Every time matter is ejected from an object and the object moves in the opposite direction, jet motion is observed. To lift objects into the air, engineers must design a powerful rocket launcher. Releasing jets of flame, the rocket's engines lift it into Earth's orbit. Sometimes rockets launch satellites and space probes.

As for airliners and military aircraft, the principle of their operation is somewhat reminiscent of a rocket taking off: physical body reacts to a powerful jet of gas ejected, as a result of which it moves in the opposite direction. This is the basic operating principle of jet aircraft.

Newton's laws of jet propulsion

Engineers base their developments on the principles of the structure of the universe, first described in detail in the works of the outstanding British scientist Isaac Newton, who lived at the end of the 17th century. Newton's laws describe the mechanisms of gravity and tell us what happens when objects move. They explain especially clearly the movement of bodies in space.

Newton's second law states that the force of a moving object depends on how much matter it contains, in other words, its mass and the change in speed of motion (acceleration). This means that in order to create a powerful rocket, it is necessary for it to constantly release large number high speed energy. Newton's third law states that for every action there will be an equal but opposite reaction - a reaction. Jet engines in nature and technology obey these laws. In the case of a rocket, the force is the matter that comes out of the exhaust pipe. The reaction is to push the rocket forward. It is the force of the emissions from it that pushes the rocket. In space, where a rocket has virtually no weight, even a slight push from rocket engines can cause big ship fly forward quickly.

Technique using jet propulsion

The physics of jet propulsion is that acceleration or deceleration of a body occurs without the influence of surrounding bodies. The process occurs due to the separation of part of the system.

Examples of jet propulsion in technology are:

1. the phenomenon of recoil from a shot;
2. explosions;
3. impacts during accidents;
4. recoil when using a powerful fire hose;
5. boat with a jet engine;
6. jet plane and rocket.

Bodies are created closed system, if they interact only with each other. Such interaction can lead to a change in the mechanical state of the bodies forming the system.

What is the effect of the law of conservation of momentum?

This law was first announced by the French philosopher and physicist R. Descartes. When two or more bodies interact, a closed system is formed between them. When moving, any body has its own momentum. This is the mass of a body multiplied by its speed. The total momentum of the system is equal to the vector sum of the momenta of the bodies located in it. The momentum of any of the bodies inside the system changes due to their mutual influence. The total momentum of bodies in a closed system remains unchanged under various movements and interactions of bodies. This is the law of conservation of momentum.

Examples of the operation of this law can be any collision of bodies (billiard balls, cars, elementary particles), as well as body explosions and shooting. When a weapon is fired, recoil occurs: the projectile rushes forward, and the weapon itself is pushed back. Why is this happening? The bullet and the weapon form between themselves closed system, where the law of conservation of momentum works. When firing, the impulses of the weapon itself and the bullet change. But the total impulse of the weapon and the bullet in it before firing will be equal to the total impulse of the recoiling weapon and the fired bullet after firing. If the bullet and the gun had the same mass, they would fly in opposite directions at the same speed.

The law of conservation of momentum has a wide range of practical application. It allows us to explain the jet motion, thanks to which the highest speeds are achieved.

Jet propulsion in physics

The most striking example of the law of conservation of momentum is the jet motion carried out by a rocket. The most important part of the engine is the combustion chamber. In one of its walls there is a jet nozzle, adapted to release gas generated during fuel combustion. Under the influence high temperature and gas pressure comes out of the engine nozzle at high speed. Before a rocket launches, its momentum relative to the Earth is zero. At the moment of launch, the rocket also receives an impulse, which is equal to the impulse of the gas, but opposite in direction.

An example of jet propulsion physics can be seen everywhere. During a birthday celebration balloon may well become a rocket. How? Inflate the balloon by pinching the open hole to prevent air from escaping. Now let him go. Balloon will race around the room at great speed, driven by the air flying out of it.

History of jet propulsion

The history of jet engines dates back to 120 years BC, when Heron of Alexandria designed the first jet engine, the aeolipile. Water is poured into a metal ball and heated by fire. The steam that escapes from this ball rotates it. This device shows jet propulsion. The priests successfully used Heron's engine to open and close temple doors. A modification of the aeolipile is the Segner wheel, which is effectively used in our time for watering agricultural land. In the 16th century, Giovani Branca introduced the world to the first steam turbine, which worked on the principle of jet propulsion. Isaac Newton proposed one of the first designs for a steam car.

The first attempts to use jet propulsion in technology for moving on land date back to the 15-17 centuries. Even 1000 years ago, the Chinese had rockets that they used as military weapons. For example, in 1232, according to the chronicle, in the war with the Mongols they used arrows equipped with rockets.

The first attempts to build a jet aircraft began in 1910. The basis was taken from rocket research of past centuries, which described in detail the use of powder accelerators that could significantly reduce the length of the afterburner and take-off run. The chief designer was the Romanian engineer Henri Coanda, who built an aircraft powered by a piston engine. The pioneer of jet propulsion in technology can rightfully be called an engineer from England - Frank Whittle, who proposed the first ideas for creating a jet engine and received his patent for them in late XIX century.

The first jet engines

The development of a jet engine in Russia first began at the beginning of the 20th century. The theory of the movement of jet vehicles and rocketry capable of reaching supersonic speed was put forward by the famous Russian scientist K. E. Tsiolkovsky. The talented designer A. M. Lyulka managed to bring this idea to life. It was he who created the project for the first jet aircraft in the USSR, powered by a jet turbine. The first jet aircraft were created by German engineers. Project creation and production were carried out secretly in disguised factories. Hitler, with his idea of ​​becoming a world ruler, recruited the best designers in Germany to produce powerful weapons, including high-speed aircraft. The most successful of these was the first German jet aircraft, the Messerschmitt 262. This aircraft became the first in the world to successfully pass all the tests, take off freely and then begin to be mass-produced.

The aircraft had the following features:

• The device had two turbojet engine.
• A radar was located in the bow.
• The maximum speed of the aircraft reached 900 km/h.

Thanks to all these indicators and design features The first jet aircraft, the Messerschmitt 262, was a formidable weapon in the fight against other aircraft.

Prototypes of modern airliners

In the post-war period, Russian designers created jet aircraft, which later became prototypes of modern airliners.

The I-250, better known as the legendary MiG-13, is a fighter that A. I. Mikoyan worked on. The first flight was made in the spring of 1945, at that time the jet fighter showed a record speed of 820 km/h. The MiG-9 and Yak-15 jet aircraft were put into production.

In April 1945, P. O. Sukhoi’s Su-5 jet aircraft took to the skies for the first time, rising and flying due to an air-breathing motor-compressor and piston engine located in the rear part of the structure.

After the end of the war and surrender fascist Germany The Soviet Union received German aircraft with JUMO-004 and BMW-003 jet engines as trophies.

First world prototypes

Not only German and Soviet designers were involved in the development, testing of new airliners and their production. Engineers from the USA, Italy, Japan, and Great Britain also created many successful projects using jet propulsion in technology. Some of the first developments with various types of engines include:

• The He-178 is a German turbojet-powered aircraft that took flight in August 1939.
• GlosterE. 28/39 - an aircraft originally from Great Britain, with a turbojet engine, first took to the skies in 1941.
• The He-176, a fighter aircraft created in Germany using a rocket engine, made its first flight in July 1939.
• BI-2 is the first Soviet aircraft that was propelled by a rocket propulsion system.
• CampiniN.1 is a jet aircraft created in Italy, which became the first attempt by Italian designers to move away from the piston counterpart.
• Yokosuka MXY7 Ohka (“Oka”) with a Tsu-11 engine is a Japanese fighter-bomber, a so-called disposable aircraft with a kamikaze pilot on board.

The use of jet propulsion in technology served as a sharp impetus for the rapid creation of the following jet aircraft and further development military and civil aircraft construction.

1. The GlosterMeteor, an air-jet fighter manufactured in Great Britain in 1943, played a significant role in the Second World War, and after its conclusion it served as an interceptor of German V-1 missiles.
2. The Lockheed F-80 is a jet aircraft manufactured in the USA using an AllisonJ engine. These aircraft took part more than once in the Japanese-Korean War.
3. The B-45 Tornado is a prototype of the modern American B-52 bomber, created in 1947.
4. The MiG-15, a successor to the acclaimed MiG-9 jet fighter, which actively participated in the military conflict in Korea, was produced in December 1947.
5. Tu-144 is the first Soviet supersonic air-jet passenger aircraft.

Modern jet vehicles

Airliners are improving every year, as designers from all over the world are working to create a new generation of aircraft capable of flying at the speed of sound and at supersonic speeds. Now there are airliners that can accommodate a large number of passengers and cargo, have enormous sizes and unimaginable speeds of over 3000 km/h, and military aircraft equipped with modern combat equipment.

But among this diversity there are several designs of record-breaking jet aircraft:

1. The Airbus A380 is the most spacious aircraft, capable of accommodating 853 passengers, which is ensured by its double-deck design. It is also one of the most luxurious and expensive airliners of our time. The largest passenger airliner in the air.
2. Boeing 747 - for more than 35 years was considered the most spacious double-decker airliner and could carry 524 passengers.
3. The AN-225 Mriya is a cargo aircraft that boasts a payload capacity of 250 tons.
4. LockheedSR-71 is a jet aircraft that reaches a speed of 3529 km/h during flight.

Aviation research does not stand still, because jet aircraft are the basis of rapidly developing modern aviation. Currently, several Western and Russian manned, passenger, and unmanned airliners with jet engines are being designed, the release of which is planned for the next few years.

To Russian innovative developments of the future can be attributed to the 5th generation fighter PAK FA - T-50, the first copies of which will enter the troops presumably at the end of 2017 or beginning of 2018 after testing a new jet engine.

Nature is an example of jet propulsion

The reactive principle of movement was initially suggested by nature itself. Its effect is used by the larvae of some types of dragonflies, jellyfish, and many mollusks - scallops, cuttlefish, octopuses, and squid. They apply a kind of “repulsion principle”. Cuttlefish draw in water and throw it out so quickly that they themselves make a leap forward. Squids using this method can reach speeds of up to 70 kilometers per hour. That is why this method of movement made it possible to call squids “biological rockets.” Engineers have already invented an engine that works on the principle of squid movements. One example of the use of jet propulsion in nature and technology is a water cannon.

This is a device that provides movement using the force of water thrown out under strong pressure. In the device, water is pumped into the chamber and then released from it through a nozzle, and the vessel moves in the opposite direction to the jet emission. Water is drawn in using an engine running on diesel or gasoline.

The plant world also offers us examples of jet propulsion. Among them there are species that use such movement to disperse seeds, for example, the mad cucumber. Only externally this plant is similar to the cucumbers we are used to. And it received the characteristic “mad” because of its strange method of reproduction. When ripe, the fruits bounce off the stalks. Eventually, a hole opens through which the cucumber shoots a substance containing seeds suitable for germination using reactivity. And the cucumber itself bounces up to twelve meters in the direction opposite to the shot.

The manifestation of jet propulsion in nature and technology is subject to the same laws of the universe. Humanity is increasingly using these laws to achieve its goals not only in the Earth's atmosphere, but also in the vastness of space, and jet propulsion is a striking example of this.

Slide 2

Application of jet propulsion in nature

Many of us in our lives have encountered jellyfish while swimming in the sea. But few people thought that jellyfish also use jet propulsion to move. And often the efficiency of marine invertebrate animals when using jet propulsion is much higher than that of technological inventions.

Slide 3

Jet propulsion is used by many mollusks - octopuses, squids, cuttlefish.

Slide 4

Cuttlefish

Cuttlefish, like most cephalopods, moves in water in the following way. She takes water into the gill cavity through a side slit and a special funnel in front of the body, and then energetically throws out a stream of water through the funnel. The cuttlefish directs the funnel tube to the side or back and, quickly squeezing water out of it, can move in different directions.

Slide 5

Squid

Squids have achieved the highest perfection in jet navigation. Even their body, with its external forms, copies the rocket (or better said, the rocket copies the squid, since it has indisputable priority in this matter)

Slide 6

The squid is the largest invertebrate inhabitant of the ocean depths. It moves according to the principle of jet propulsion, absorbing water, and then pushing it with enormous force through a special hole - a “funnel”, and at high speed (about 70 km/h) it pushes backwards. At the same time, all ten tentacles of the squid are gathered into a knot above its head and it takes on a streamlined shape.

Slide 7

Flying squid

This is a small animal about the size of a herring. It chases fish with such speed that it often jumps out of the water, skimming over its surface like an arrow. Having developed maximum jet thrust in the water, the pilot squid takes off into the air and flies over the waves for more than fifty meters. The apogee of a living rocket's flight lies so high above the water that flying squids often end up on the decks of ocean-going ships. Four to five meters is not a record height to which squids rise into the sky. Sometimes they fly even higher.

Slide 8

Octopus

Octopuses can also fly. French naturalist Jean Verani saw how an ordinary octopus accelerated in an aquarium and suddenly jumped out of the water backwards. Having described an arc about five meters long in the air, he plopped back into the aquarium. When picking up speed to jump, the octopus moved not only due to jet thrust, but also rowed with its tentacles.

There are various types movement as a way of moving bodies from one point in space to another. in nature and technology, which occurs when a part of it is separated from the body at any speed, is certainly less common, but still occupies its rightful place. And in technology, scientists actually “spied” jet propulsion from living nature. And they used it quite successfully in their inventions. Our material will tell you about this and much more, no less interesting.

Reactivity in animals

For example, swimming in sea ​​wave, many people often came face to face with representatives of aquatic fauna - jellyfish. But few people thought that these animals use a reactive type for movement. Also, marine plankton and the larvae of some insect species move using reactivity. And, by the way, in technology, jet propulsion, or rather its efficiency, is sometimes much lower than that of these creations of nature.

Many shellfish also use it. And they move, for example, due to the reactivity of the stream of water released from the animal’s shell when the valves are compressed. The squid still has something skillfully developed by nature. Due to this, it moves abruptly in the aquatic environment, and sometimes this marine inhabitant even takes off into the air!

Jet propulsion in technology. Examples

This method is also widely used in the modern era. It should be noted that in technology, reactive movement largely copies natural reactivity. Even in ancient times in China (first millennium AD), bamboo pipes filled with gunpowder were invented, which were used mainly for fun. They were based on the reactive principle. And Newton at one time came up with not only the same name but also the prototype of a car that was equipped with a jet engine.

For human flight

People realized that jet propulsion could be used in technology for flight. The first author of such a project is considered to be the Narodnaya Volya member Kibalchich, who literally a few days before his death (he was sentenced to death as a participant in the assassination attempt on the Tsar) developed and recorded scientific data. Tsiolkovsky developed Kibalchich's ideas and developed a mathematical equation that was important for astronautics, allowing the use of the reactivity principle. It was he who described in his works the principles of operation of jet units using liquid fuel.

Jet engine

In its design, it converts fuel chemical energy into kinetic energy - already a gas jet. In this case, the speed of the opposite direction is acquired. Tsiolkovsky's ideas were developed by Korolev, and the launch of the first satellite using it was carried out in 1957 in the USSR. And the first person to overcome gravity with the help of jet propulsion was Soviet pilot Gagarin in 1961. He flew around the planet on the Vostok spacecraft.

Rocket device

To put it simply, a modern launch vehicle consists of a shell and fuel (plus an oxidizer). The shell contains a payload - a space capsule, which is launched into Earth orbit. Control devices and the engine are also located here. The rest of the useful area of ​​the rocket is occupied by fuel and an oxidizer designed to support the combustion process (after all, there is no oxygen in space).

In the combustion chamber, the fuel is converted into gas under high pressure and very high temperatures. Due to the difference in pressure outside the spacecraft and in the combustion chambers, the gas rushes out, due to which the rocket moves.

Jet propulsion in nature and technology

ABSTRACT ON PHYSICS

Jet propulsion- movement that occurs when any part of it is separated from the body at a certain speed.

Reactive force occurs without any interaction with external bodies.

Application of jet propulsion in nature

Many of us in our lives have encountered jellyfish while swimming in the sea. In any case, there are quite enough of them in the Black Sea. But few people thought that jellyfish also use jet propulsion to move. In addition, this is how dragonfly larvae and some types of marine plankton move. And often the efficiency of marine invertebrate animals when using jet propulsion is much higher than that of technological inventions.

Jet propulsion is used by many mollusks - octopuses, squids, cuttlefish. For example, a sea scallop mollusk moves forward due to the reactive force of a stream of water thrown out of the shell during a sharp compression of its valves.

Octopus

Cuttlefish

Cuttlefish, like most cephalopods, moves in water in the following way. She takes water into the gill cavity through a side slit and a special funnel in front of the body, and then energetically throws out a stream of water through the funnel. The cuttlefish directs the funnel tube to the side or back and, quickly squeezing water out of it, can move in different directions.

The salpa is a marine animal with a transparent body; when moving, it receives water through the front opening, and the water enters a wide cavity, inside of which the gills are stretched diagonally. As soon as the animal takes a large sip of water, the hole closes. Then the longitudinal and transverse muscles of the salp contract, the whole body contracts, and water is pushed out through the posterior opening. The reaction of the escaping jet pushes the salpa forward.

The squid's jet engine is of greatest interest. The squid is the largest invertebrate inhabitant of the ocean depths. Squids have achieved the highest perfection in jet navigation. Even their body, with its external forms, copies the rocket (or better said, the rocket copies the squid, since it has indisputable priority in this matter). When moving slowly, the squid uses a large diamond-shaped fin that periodically bends. It uses a jet engine to throw quickly. Muscle tissue - the mantle surrounds the mollusk's body on all sides; the volume of its cavity is almost half the volume of the squid's body. The animal sucks water inside the mantle cavity, and then sharply throws out a stream of water through a narrow nozzle and moves backwards with high speed pushes. At the same time, all ten tentacles of the squid are gathered into a knot above its head, and it takes on a streamlined shape. The nozzle is equipped with a special valve, and the muscles can rotate it, changing the direction of movement. The squid engine is very economical, it is capable of reaching speeds of up to 60 - 70 km/h. (Some researchers believe that even up to 150 km/h!) No wonder the squid is called a “living torpedo.” By bending the bundled tentacles to the right, left, up or down, the squid turns in one direction or another. Since such a rudder is very large compared to the animal itself, its slight movement is enough for the squid, even at full speed ahead, could easily dodge a collision with an obstacle. A sharp turn of the steering wheel - and the swimmer rushes in the opposite direction. So he bent the end of the funnel back and now slides head first. He bent it to the right - and the jet push threw him to the left. But when you need to swim quickly, the funnel always sticks out right between the tentacles, and the squid rushes tail first, just as a crayfish would run - a fast walker endowed with the agility of a horse.

If there is no need to rush, squids and cuttlefish swim, undulating their fins - miniature waves run over them from front to back, and the animal glides gracefully, occasionally pushing itself also with a stream of water thrown out from under the mantle. Then the individual shocks that the mollusk receives at the moment of eruption of water jets are clearly visible. Some cephalopods can reach speeds of up to fifty-five kilometers per hour. It seems that no one has made direct measurements, but this can be judged by the speed and flight range of flying squids. And it turns out that octopuses have such talents in their family! The best pilot among mollusks is the squid Stenoteuthis. English sailors call it flying squid (“flying squid”). This is a small animal about the size of a herring. It chases fish with such speed that it often jumps out of the water, skimming over its surface like an arrow. He resorts to this trick to save his life from predators - tuna and mackerel. Having developed maximum jet thrust in the water, the pilot squid takes off into the air and flies over the waves for more than fifty meters. The apogee of a living rocket's flight lies so high above the water that flying squids often end up on the decks of ocean-going ships. Four to five meters is not a record height to which squids rise into the sky. Sometimes they fly even higher.

The English mollusk researcher Dr. Rees described in a scientific article a squid (only 16 centimeters long), which, having flown a fair distance through the air, fell on the bridge of a yacht, which rose almost seven meters above the water.

It happens that a lot of flying squids fall on the ship in a sparkling cascade. The ancient writer Trebius Niger once told a sad story about a ship that allegedly sank under the weight of flying squids that fell on its deck. Squids can take off without acceleration.

Octopuses can also fly. French naturalist Jean Verani saw how an ordinary octopus accelerated in an aquarium and suddenly jumped out of the water backwards. Having described an arc about five meters long in the air, he plopped back into the aquarium. When picking up speed to jump, the octopus moved not only due to jet thrust, but also rowed with its tentacles.
Baggy octopuses swim, of course, worse than squids, but at critical moments they can show a record class for the best sprinters. California Aquarium staff tried to photograph an octopus attacking a crab. The octopus rushed at its prey with such speed that the film, even when filming at the highest speeds, always contained grease. This means that the throw lasted hundredths of a second! Typically, octopuses swim relatively slowly. Joseph Seinl, who studied the migrations of octopuses, calculated: an octopus half a meter in size swims through the sea at an average speed of about fifteen kilometers per hour. Each jet of water thrown out of the funnel pushes it forward (or rather, backward, since the octopus swims backwards) two to two and a half meters.

Jet motion can also be found in the plant world. For example, the ripe fruits of the “mad cucumber”, with the slightest touch, bounce off the stalk, and a sticky liquid with seeds is forcefully thrown out of the resulting hole. The cucumber itself flies off in the opposite direction up to 12 m.

Knowing the law of conservation of momentum, you can change your own speed of movement in open space. If you are in a boat and you have several heavy stones, then throwing stones in a certain direction will move you in the opposite direction. The same will happen in outer space, but there they use jet engines for this.

Everyone knows that a shot from a gun is accompanied by recoil. If the weight of the bullet were equal to the weight of the gun, they would fly apart at the same speed. Recoil occurs because the ejected mass of gases creates a reactive force, thanks to which movement can be ensured both in air and in airless space. And the greater the mass and speed of the flowing gases, the greater the recoil force our shoulder feels, the stronger the reaction of the gun, the greater the reactive force.

Application of jet propulsion in technology

For many centuries, humanity has dreamed of space flight. Science fiction writers have proposed a variety of means to achieve this goal. In the 17th century, a story by the French writer Cyrano de Bergerac about a flight to the moon appeared. The hero of this story reached the Moon in an iron cart, over which he constantly threw a strong magnet. Attracted to him, the cart rose higher and higher above the Earth until it reached the Moon. And Baron Munchausen said that he climbed to the moon along a bean stalk.

At the end of the first millennium AD, China invented jet propulsion, which powered rockets - bamboo tubes filled with gunpowder, they were also used as fun. One of the first car projects was also with a jet engine and this project belonged to Newton

The author of the world's first project of a jet aircraft intended for human flight was the Russian revolutionary N.I. Kibalchich. He was executed on April 3, 1881 for his participation in the assassination attempt on Emperor Alexander II. He developed his project in prison after being sentenced to death. Kibalchich wrote: “While in prison, a few days before my death, I am writing this project. I believe in the feasibility of my idea, and this faith supports me in my terrible situation... I will calmly face death, knowing that my idea will not die with me.”

The idea of ​​using rockets for space flights was proposed at the beginning of this century by the Russian scientist Konstantin Eduardovich Tsiolkovsky. In 1903, an article by Kaluga gymnasium teacher K.E. appeared in print. Tsiolkovsky “Exploration of world spaces using reactive instruments.” This work contained the most important mathematical equation for astronautics, now known as the “Tsiolkovsky formula,” which described the motion of a body of variable mass. Subsequently, he developed a design for a liquid-fuel rocket engine, proposed a multi-stage rocket design, and expressed the idea of ​​​​the possibility of creating entire space cities in low-Earth orbit. He showed that the only device capable of overcoming gravity is a rocket, i.e. a device with a jet engine that uses fuel and oxidizer located on the device itself.

Jet engine is an engine that converts the chemical energy of fuel into the kinetic energy of a gas jet, while the engine acquires speed in the opposite direction.

The idea of ​​K.E. Tsiolkovsky was implemented by Soviet scientists under the leadership of Academician Sergei Pavlovich Korolev. The first artificial Earth satellite in history was launched by rocket in the Soviet Union on October 4, 1957.

The principle of jet propulsion finds wide practical application in aviation and astronautics. In outer space there is no medium with which a body could interact and thereby change the direction and magnitude of its speed, therefore only jet aircraft, i.e., rockets, can be used for space flights.

Rocket device

The motion of a rocket is based on the law of conservation of momentum. If at some point in time any body is thrown away from the rocket, it will acquire the same impulse, but directed in the opposite direction

Any rocket, regardless of its design, always has a shell and fuel with an oxidizer. The rocket shell includes the payload (in this case the spacecraft), the instrument compartment and the engine (combustion chamber, pumps, etc.).

The main mass of the rocket is fuel with an oxidizer (the oxidizer is needed to maintain fuel combustion, since there is no oxygen in space).

Fuel and oxidizer are supplied to the combustion chamber using pumps. When fuel burns, it turns into high temperature gas and high pressure. Due to the large pressure difference in the combustion chamber and in outer space, gases from the combustion chamber rush out in a powerful jet through a specially shaped socket called a nozzle. The purpose of the nozzle is to increase the speed of the jet.

Before the rocket launches, its momentum equal to zero. As a result of the interaction of the gas in the combustion chamber and all other parts of the rocket, the gas escaping through the nozzle receives some impulse. Then the rocket is a closed system, and its total momentum must be zero after launch. Therefore, the entire shell of the rocket that is in it receives an impulse equal in magnitude to the impulse of the gas, but opposite in direction.

The most massive part of the rocket, intended for launch and acceleration of the entire rocket, is called the first stage. When the first massive stage of a multi-stage rocket exhausts all its fuel reserves during acceleration, it separates. Further acceleration is continued by the second, less massive stage, and it adds some more speed to the speed previously achieved with the help of the first stage, and then separates. The third stage continues to increase speed to the required value and delivers the payload into orbit.

The first person to fly in outer space was a citizen Soviet Union Yuri Alekseevich Gagarin. April 12, 1961 He circled the globe on the Vostok satellite.

Soviet rockets were the first to reach the Moon, circled the Moon and photographed its side invisible from Earth, and were the first to reach the planet Venus and deliver scientific instruments to its surface. In 1986, two Soviet spaceship Vega 1 and Vega 2 closely examined Halley's Comet, which approaches the Sun once every 76 years.