Post on jet propulsion in technology. Biophysics: jet propulsion in wildlife. Reactive way of moving jellyfish

Today, most people associate jet propulsion in the first place, of course, with the latest scientific and technological developments. We know from physics textbooks that "reactive" means movement that occurs as a result of the separation of any part from an object (body). The man wanted to rise into the sky to the stars, he strove to fly, but he was able to fulfill his dream only with the appearance jet aircraft and stepped spaceships capable of traveling over great distances, accelerating to supersonic speeds, thanks to the modern jet engines installed on them. Designers and engineers developed the possibility of using jet propulsion in engines. Scientists also did not stand aside, offering the most incredible ideas and ways to achieve this goal. Surprisingly, this principle of movement is widespread in nature. It is enough to look around, you can notice the inhabitants of the seas and land, among which there are plants, the movement of which is based on the reactive principle.

History

Even in ancient times, scientists with interest studied and analyzed the phenomena associated with jet propulsion in nature. One of the first to theoretically substantiate and describe its essence was Heron, a mechanic and theorist of Ancient Greece, who invented the first steam engine, named after him. The Chinese were able to find practical use for the reactive method. They were the first, taking as a basis the method of movement of cuttlefish and octopuses, in the 13th century they invented rockets. They were used in fireworks, making a great impression, and as signal flares, there may have been combat missiles, which were used as rocket artillery. Over time, this technology also came to Europe.

N. Kibalchich became the discoverer of modern times, having come up with a prototype scheme aircraft with a jet engine. He was an outstanding inventor and a staunch revolutionary, for which he was imprisoned. It was while in prison that he went down in history by creating his project. After his execution for active revolutionary activities and opposition to the monarchy, his invention was forgotten on the archival shelves. After some time, K. Tsiolkovsky was able to improve the ideas of Kibalchich, proving the possibility of exploring outer space by means of jet movement of spaceships.

Later, during the Great Patriotic War, the famous Katyushas, \u200b\u200bfield rocket artillery systems, appeared. This is how the people unofficially called the powerful installations that were used by the forces of the USSR with an affectionate name. It is not known for certain, in connection with which, the weapon received this name. The reason for this was either the popularity of Blanter's song, or the letter "K" on the body of the mortar. Over time, the front-line soldiers began to give nicknames to other weapons, thus creating a new tradition. The Germans also called this combat rocket launcher "Stalin's organ" for appearance, which resembled a musical instrument and a shrill sound that came from launching rockets.

Vegetable world

Representatives of the fauna also use the laws of jet propulsion. Most of the plants with such properties are annuals and juveniles: prickly fruit, petiolate garlic, touch-me-not core, double-cut pickle, three-veined meringia.

The prickly carp, aka mad cucumber, belongs to the pumpkin family. This plant grows to a large size, has a thick root with a rough stem and large leaves. It grows in the territory of Central Asia, the Mediterranean, in the Caucasus, quite common in the south of Russia and Ukraine. Inside the fruit, during the period of seed ripening, it is converted into mucus, which, under the influence of temperatures, begins to ferment and release gas. Closer to ripening, the pressure inside the fetus can reach 8 atmospheres. Then, with a light touch, the fruit breaks off from the base and the seeds with liquid at a speed of 10 m / s fly out of the fruit. Due to its ability to shoot up to 12 m in length, the plant was named "lady's pistol".

The touch-me-not core is an annual widespread species. It is found, as a rule, in shady forests, along the banks along rivers. Once in the northeastern part of North America and South Africa, it successfully took root. The touch-sensitive core is propagated by seeds. The seeds of the touch-me-not core are small, weighing no more than 5 mg, which are thrown at a distance of 90 cm. Thanks to this method of seed distribution, the plant got its name.

Animal world

Jet propulsion — interesting Factsconcerning the animal world. In cephalopods, reactive movement occurs by means of water exhaled through a siphon, which usually narrows to a small opening to obtain maximum expiratory flow. Water flows through the gills before exhalation, fulfilling the dual purpose of breathing and moving. Sea hares, otherwise gastropods, use similar means of movement, but without the complex neurological apparatus of cephalopods, they move more awkwardly.

Some knight fish have also evolved jet propulsion by pumping water through their gills to complement their fin movement.

In dragonfly larvae, reactive force is achieved by displacing water from a specialized cavity in the body. Scallops and cardids, siphonophores, tunics (such as salps) and some jellyfish also use jet propulsion.

Most of the time, scallops lie quietly on the bottom, but in case of danger, they quickly close the valves of their shells, so they push out the water. This behavior mechanism also speaks of the use of the principle of reactive movement. Thanks to him, the scallops can float and move a great distance, using the technique of opening and closing the shell.

The squid also uses this method, absorbs water, and then with tremendous force pushing through the funnel moves at a speed of at least 70 km / h. Gathering the tentacles into one knot, the body of the squid forms a streamlined shape. Taking such a squid engine as a basis, the engineers have designed a water cannon. Water in it is sucked into the chamber, and then thrown out through the nozzle. Thus, the vessel is directed in the opposite direction from the ejected jet.

Compared to squid, salps use the most efficient engines, spending an order of magnitude less energy than squid. Moving, the salpa launches water into the opening in front, and then enters a wide cavity where the gills are stretched. After the pharynx, the opening is closed, and with the help of contracting longitudinal and transverse muscles that compress the body, water is ejected through the opening from behind.

The most unusual of all locomotion mechanisms is the common cat. Marcel Despres suggested that the body is able to move and change its position even with the help of only internal forces (not starting from anything and not relying on anything), from which it could be concluded that Newton's laws may be wrong. The proof of his hypothesis could be a cat that fell from a height. During the fall upside down, it will still land on all its paws, this has already become a kind of axiom. Having photographed in detail the movement of the cat, we were able to see in frames everything that it was doing in the air. We saw her paw movement, which caused a response from the trunk, turning in the other direction relative to the movement of the paw. Acting in accordance with Newton's laws, the cat landed successfully.

In animals, everything happens at the level of instinct, man, in turn, does it consciously. Professional swimmers, having jumped from the tower, manage to turn around three times in the air, and, having managed to stop the rotation, they straighten strictly vertically and dive into the water. The same principle applies to circus aerialists.

No matter how much a person tries to surpass nature, improving the inventions created by it, all the same, we have not yet reached the technological perfection when airplanes could repeat the actions of a dragonfly: hover in the air, instantly move backwards or move to the side. And all this happens at high speed. Perhaps a little more time will pass and planes, thanks to adjustments for the aerodynamics and jet capabilities of dragonflies, will be able to make sharp turns and become less susceptible to external conditions. Having looked at nature, a person can still improve a lot for the benefit of technological progress.

Reactive motion in nature ”.

Completed by the student:

10 "A" class

Kaklyugina Ekaterina.

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

Many of us in our life have met while swimming in the sea with jellyfish. In any case, there are enough of them in the Black Sea. But few people thought that jellyfish use jet propulsion for movement. In addition, this is how the larvae of dragonflies and some species of marine plankton move. And often the efficiency of marine invertebrates using jet propulsion is much higher than that of techno inventions.

Jet propulsion is used by many molluscs - octopuses, squid, cuttlefish. For example, a scallop clam moves forward due to the reactive force of a stream of water ejected from a shell when its valves are sharply compressed.

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

Jet propulsion can also be found in the plant world. For example, ripe fruits of "mad cucumber" at the slightest touch bounce off the stalk, and a sticky liquid with seeds is thrown out of the hole with force. At the same time, the cucumber itself flies 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 have several heavy stones, then by throwing stones in a certain direction, you will move 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 a recoil. If the weight of the bullet were equal to the weight of the gun, they would fly at the same speed. Recoil occurs because the rejected mass of gases creates a reactive force, thanks to which movement can be provided both in air and in airless space. And the greater the mass and velocity of the outflowing 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, mankind has dreamed of space travel. Science fiction writers have offered a variety of means to achieve this goal. In the 17th century, the story of the French writer Cyrano de Bergerac about the flight to the moon appeared. The hero of this story got to the moon in an iron cart, over which he constantly tossed a strong magnet. Pulling towards him, the wagon rose higher and higher above the Earth until it reached the moon. And Baron Munchausen said that he climbed to the moon on a bean stalk.

At the end of the first millennium AD, China invented jet propulsion, which propelled 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 designed for human flight was the Russian revolutionary N.I. Kibalchich. He was executed on April 3, 1881 for participating in the assassination attempt on Emperor Alexander II. He developed his project in prison after the death sentence. 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 belief supports me in my terrible situation ... I will calmly face death, knowing that my idea will not perish with me. " The idea of \u200b\u200busing rockets for space flights was proposed at the beginning of this century by the Russian scientist Konstantin Eduardovich Tsiolkovsky. In 1903, an article by the teacher of the Kaluga gymnasium K.E. Tsiolkovsky "Exploration of world spaces with jet devices". This work contained the most important for cosmonautics mathematical equation, now known as the "Tsiolkovsky formula", which described the motion of a body of variable mass. Subsequently, he developed a rocket engine scheme for liquid fuel, proposed a multistage rocket design, expressed the idea of \u200b\u200bthe possibility of creating entire space cities in near-earth orbit. He showed that the only device capable of overcoming gravity is a rocket, i.e. apparatus with a jet engine using fuel and an oxidizer located on the apparatus itself.

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

What is jet propulsion?

On english language the word "jet" sounds like "jet". It means the movement of a body, which is formed in the process of separating a part from it at a certain speed. A force is manifested that moves the body in the opposite direction from the direction of movement, separating a part from it. Every time matter is pulled out of the object, and the object moves in the opposite direction, there is a jet motion. In order to lift objects into the air, engineers must design a powerful rocket launcher. By 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: the physical body reacts to the ejected powerful jet of gas, as a result of which it moves in the opposite direction. This is the basic principle of jet aircraft.

Newton's laws in jet propulsion

Engineers base their developments on the principles 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 about what happens when things move. They explain the movement of bodies in space especially clearly.

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

Technique using jet propulsion

The physics of jet propulsion is that the acceleration or deceleration of a body occurs without the influence of the 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. blows during accidents;
4. recoil when using a powerful fire hose;
5. a boat with a water-jet engine;
6. jet plane and rocket.

Bodies create a closed system if they only interact with each other. Such interaction can lead to a change in the mechanical state of the bodies that form the system.

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

For the first time this law was announced by the French philosopher and physicist R. Descartes. When two or more bodies interact, a closed system is formed between them. Any body in motion has its own impulse. This is the mass of the body multiplied by its speed. The total impulse of the system is equal to the vector sum of the impulses of the bodies 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 for various displacements and interactions of bodies. This is the momentum conservation law.

Examples of the operation of this law can be any collisions of bodies (billiard balls, cars, elementary particles), as well as bursting of bodies and shooting. When a weapon is fired, a recoil occurs: the projectile rushes forward, and the weapon itself is pushed back. Why is this happening? The bullet and the weapon form a closed system with each other, 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 inside it before firing will be equal to the total impulse of the rolling weapon and the bullet fired after firing. If the bullet and the gun had the same mass, they would fly in opposite directions at the same speed.

The momentum conservation law has wide practical application. It helps to explain the jet propulsion, due to which the highest speeds are achieved.

Reactive motion in physics

The most striking example of the law of conservation of momentum is the jet propulsion 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 for the release of gas arising from the combustion of fuel. Under the influence of high temperature and pressure, the gas exits the engine nozzle at high speed. Before the launch of the rocket, its momentum relative to the Earth is equal to zero. At the moment of launch, the rocket also receives an impulse that is equal to the impulse of the gas, but opposite in direction.

An example of the physics of jet propulsion can be seen everywhere. During a birthday celebration, a balloon can easily become a rocket. How? Inflate the balloon by pinching the open hole to keep air from escaping. Now release it. Balloon with great speed it will drive around the room, driven by the air flying out of it.

History of jet propulsion

The history of jet engines began as early as 120 years BC, when Heron of Alexandria designed the first jet engine - eolipil. Water is poured into a metal ball, which is heated by fire. The steam that escapes from this ball rotates it. This device shows jet propulsion. The priests used the engine of Heron to open and close the doors of the temple. Modification of eolipil - Segner wheel, which is effectively used in our time for irrigation of agricultural land. In the 16th century, Giovani Branca introduced the world to the first steam turbine that operated 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 to move on the ground date back to the 15-17 centuries. Even 1000 years ago, the Chinese had rockets that they used as military weapon... For example, in 1232, according to the chronicle, in the war with the Mongols, they used arrows equipped with missiles.

The first attempts to build a jet aircraft began in 1910. The rocket research of past centuries was taken as a basis, which described in detail the use of powder boosters, which could significantly reduce the length of the afterburner and takeoff run. The chief designer was the Romanian engineer Anri Coanda, who built an aircraft based on a piston engine. The pioneer of jet propulsion in technology can rightfully be called an engineer from England - Frank Wheatle, who proposed the first ideas for creating a jet engine and received his patent for them at the end of the 19th century.

First jet engines

For the first time, the development of a jet engine in Russia was started at the beginning of the 20th century. The theory of the motion of jet vehicles and rocketry capable of developing 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 of the first jet aircraft in the USSR, working with a jet turbine. The first jet aircraft were created by German engineers. Project creation and production were carried out in secret in disguised factories. Hitler, with his idea of \u200b\u200bbecoming a world ruler, involved the best designers in Germany to produce the most powerful weapons, including high-speed aircraft. The most successful of these was the first German jet, the Messerschmitt-262. This aircraft became the first in the world that successfully passed all the tests, took off freely and after that began to be mass-produced.

The aircraft had the following features:

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

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

Prototypes of modern airliners

In the post-war period russian designers jet aircraft were created, which later became the 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 took place 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 launched into production.

In April 1945, for the first time, the jet aircraft of P.O. Sukhoi - Su-5 took off into the sky, rising and flying due to an air-jet motor-compressor and piston engine located in the tail of the structure.

After the end of the war and the surrender of Nazi Germany The Soviet Union got as trophies german aircraft with jet engines JUMO-004 and BMW-003.

First world prototypes

Not only German and Soviet designers were involved in the development, testing and production of new airliners. Engineers from the USA, Italy, Japan, Great Britain also created a lot successful projectsused jet propulsion in engineering. Among the first developments since different types engines include:

• Non-178 is a German turbojet powered aircraft that took off in August 1939.
• GlosterE. 28/39 is an aircraft originally from the UK, with a turbojet engine, first took to the skies in 1941.
• He-176 - a fighter created in Germany using a rocket engine, made its first flight in July 1939.
• BI-2 is the first Soviet aircraft to be propelled by a rocket power plant.
• CampiniN.1 is a jet aircraft created in Italy, which was the first attempt by Italian designers to move away from the piston analogue.
• Yokosuka MXY7 Ohka ("Oka") with a Tsu-11 engine is a Japanese fighter-bomber, the 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. GlosterMeteor - a jet fighter, manufactured in Great Britain in 1943, played a significant role in the Second World War, and after its completion it served as an interceptor of German V-1 missiles.
2. The Lockheed F-80 is a US-made jet aircraft using an AllisonJ engine. These aircraft took part in the Japanese-Korean War more than once.
3. The B-45 Tornado is a prototype of modern American B-52 bombers, created in 1947.
4. The MiG-15 is a follower of the recognized 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 jet passenger aircraft.

Modern jet vehicles

Every year, airliners are improving, because 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 capable of accommodating a large number of passengers and cargo, of enormous size and an unimaginable speed of over 3000 km / h, military aircraft equipped with modern combat gear.

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

1. The Airbus A380 is the most capacious aircraft capable of accommodating 853 passengers on board, which is ensured by a double-deck structure. He is also one of the most luxurious and expensive airliners of our time. The largest passenger liner in the air.
2. Boeing 747 - for more than 35 years it was considered the most capacious double-decker liner and could carry 524 passengers.
3. AN-225 Mriya is a cargo aircraft that boasts a carrying 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 the rapidly developing modern aviation. Several Western and Russian manned, passenger, and unmanned jet-powered airliners are currently under design, with production scheduled for the next few years.

Russian innovative developments of the future include the 5th generation PAK FA - T-50 fighter, the first copies of which will arrive at the troops presumably in late 2017 or early 2018 after testing a new jet engine.

Nature is an example of jet propulsion

The reactive principle of movement was originally prompted by nature itself. Its action is used by the larvae of some species of dragonflies, jellyfish, many mollusks - scallops, cuttlefish, octopuses, squids. They use a kind of "repulsion principle". Cuttlefish suck in water and throw it out so rapidly 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 squid "biological rockets". Engineers have already invented an engine based on the movement of a squid. 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 a strong pressure. In the device, water is pumped into the chamber, and then discharged from it through the nozzle, and the vessel moves in the opposite direction of the jet ejection. The water is drawn in with a diesel or gasoline engine.

The plant world also offers examples of jet propulsion. Among them are species that use this movement to spread seeds, such as the mad cucumber. Only outwardly, this plant is similar to the cucumbers we are used to. And the characteristic "rabid" it received because of the strange way of reproduction. Ripening, the fruits bounce off the stalks. As a result, a hole opens through which the cucumber shoots a substance containing seeds suitable for germination, applying reactivity. And the cucumber itself bounces up to twelve meters to the side opposite to the shot.

The manifestation of jet propulsion in nature and technology is subject to the same laws of the universe. Mankind 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 prime example of this.

Reactive motion in nature and technology is a very common phenomenon. In nature, it occurs when one part of the body is separated at a certain rate from some other part. In this case, the reactive force appears without the interaction of this organism with external bodies.

In order to understand what is at stake, it is best to refer to examples. in nature and technology are numerous. We will first talk about how animals use it, and then how it is applied in technology.

Jellyfish, dragonfly larvae, plankton and molluscs

Many, swimming in the sea, met jellyfish. In the Black Sea, at least, there are enough of them. However, not everyone thought that jellyfish move just with the help of jet propulsion. The larvae of dragonflies, as well as some representatives of marine plankton, use the same method. 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, octopus. In particular, the scallop is able to move forward using a jet stream of water that is thrown out of the shell when its shells are sharply compressed.

And these are just a few examples from the life of the animal world, which can be cited, revealing the theme: "Reactive motion in everyday life, nature and technology."

How does cuttlefish move

Cuttlefish is also very interesting in this respect. 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 the lateral slit, the cuttlefish takes water into its gill cavity. Then she vigorously throws it out through the funnel. The cuttlefish directs the funnel tube back or sideways. In this case, movement can be carried out in different directions.

The way that salpa uses

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

Squids - "live torpedoes"

The biggest interest is, perhaps, the jet engine that the squid has. This animal is considered the most major representative invertebrates living at great ocean depths. In jet navigation, squid have reached real perfection. Even the body of these animals resembles a rocket with its external forms... Rather, this rocket copies the squid, since it is he who owns the indisputable primacy in this matter. If you need to move slowly, the animal uses a large diamond-shaped fin for this, which bends from time to time. If you need a quick throw, a jet engine comes to the rescue.

On all sides, the body of the mollusk is surrounded by a mantle - muscle tissue. Almost half of the entire volume of the animal's body falls on the volume of its cavity. The squid uses the mantle cavity for movement, sucking water inside it. Then he abruptly throws the collected stream of water through a narrow nozzle. As a result, he jerks backward with great speed. At the same time, the squid folds all of its 10 tentacles into a knot above its head in order to acquire a streamlined shape. The nozzle has a special valve, and the animal's muscles can turn it. This changes the direction of travel.

Impressive movement speed of the squid

I must say that the squid engine is very economical. The speed that he is capable of developing can reach 60-70 km / h. Some researchers even believe that it can go up to 150 km / h. As you can see, the squid is called a "live torpedo" for a reason. It can turn in the desired direction, bending down, up, left or right the tentacles folded in a bundle.

How the squid controls movement

Since the rudder is very large compared to the size of the animal itself, in order for the squid to easily avoid a collision with an obstacle, even moving at maximum speed, only a slight movement of the rudder is enough. If you turn it sharply, the animal will immediately rush in the opposite direction. The squid bends back the end of the funnel and, as a result, can slide head first. If he bends it to the right, it will be thrown to the left by a jet thrust. However, when you need to swim fast, the funnel is always right between the tentacles. In this case, the animal rushes with its tail forward, like a runaway crab, if it had the agility of a horse.

In the case when there is no need to rush, cuttlefish and squids swim, undulating with their fins. From front to back, miniature waves run over them. Squids and cuttlefish glide gracefully. They only occasionally nudge themselves with a stream of water that is thrown 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 carried out direct measurements, but we can name such a figure based on the range and speed of flight of flying squids. It turns out that there are such. Stenoteutis squid is the best pilot of all shellfish. English sailors call it a flying squid (flying squid). This animal, the photo of which is presented above, is small in size, about the size of a herring. It pursues fish so swiftly that it often jumps out of the water, sweeping like an arrow over its surface. He uses this trick in the case when he is in danger from predators - mackerels and tuna. Having developed maximum jet thrust in the water, the squid takes off into the air and then flies over 50 meters above the waves. During its flight, it is so high that often flying squids fall on the decks of ships. The height of 4-5 meters is not a record for them. Sometimes flying squids fly even higher.

Dr. Rees, a British shellfish researcher, described in his scientific article 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 yacht's bridge. And the height of this bridge was almost 7 meters!

There are times when a lot of flying squids hit the ship at once. Trebius Niger, an ancient writer, once told a sad story about a ship that seemed unable to bear 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 as one of them accelerated in his aquarium and then suddenly jumped out of the water. The animal described an arc of about 5 meters in the air, and then flopped into the aquarium. The octopus, gaining the speed necessary to jump, moved not only thanks to jet thrust. He also rowed with his tentacles. Octopuses are baggy, so they swim worse than squid, but at critical moments these animals can give odds to the best sprinters. The staff at the California Aquarium 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 the special mode, turned out to be blurry. This means that the throw lasted only a fraction of a second!

However, octopuses usually swim rather slowly. Scientist Joseph Seinle, who researched the migration of octopuses, found that the octopus, which is 0.5 m in size, swims at an average speed of about 15 km / h. Each stream of water that he throws out of the funnel moves him forward (more precisely, backward, since he floats backwards) somewhere 2-2.5 m.

"Squirting cucumber"

Reactive motion in nature and in technology can be considered and using examples from the world of plants to illustrate it. One of the most famous is the ripe fruit of the so-called They bounce off the stalk at the slightest touch. Then, from the resulting hole, a special sticky liquid is thrown out with great force, in which the seeds are located. The cucumber itself flies in the opposite direction at a distance of up to 12 m.

Momentum conservation law

It is imperative to talk about it, considering jet propulsion in nature and technology. Knowledge 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 some stones with you. If you throw them in a certain direction, the boat will move in the opposite direction. This law also operates in outer space. However, for this purpose they use

What other examples of jet propulsion in nature and technology can be noted? The law of conservation of momentum is very well illustrated by 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 happens because a reactive force is created, since there is a rejected mass. Thanks to this force, movement is provided both in an airless space and in the air. The greater the speed and mass of the outflowing gases, the greater the recoil force that our shoulder feels. Accordingly, the reactive force is the higher, the stronger the reaction of the gun.

Dreams of space travel

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

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 the flight to the moon. His hero reached the satellite of the Earth using an iron cart. Over this structure, he constantly threw a strong magnet. The cart, being attracted to him, rose higher and higher above the Earth. Eventually she reached the moon. Another famous character, Baron Munchausen, climbed a bean stalk to the moon.

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

Towards an extraordinary discovery

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

N.I. also thought about how jet propulsion in nature and technology arises. Kibalchich. This is a Russian revolutionary, the author of the first project of a jet aircraft, which is designed to fly a person on it. The revolutionary, unfortunately, was executed on April 3, 1881. Kibalchich was accused of participating in the assassination attempt on Alexander II. Already in prison, in anticipation of the execution of the death sentence, he continued to study such an interesting phenomenon as jet propulsion in nature and in technology that occurs when a part of an object is separated. As a result of these studies, he developed his own project. Kibalchich wrote that this idea supports him in his position. He is ready to calmly meet his death, knowing that such an important discovery will not perish with him.

Implementation of the idea of \u200b\u200bspace flight

K.E. Tsiolkovsky continued to study the manifestation of jet propulsion in nature and technology (his photo is presented above). At the beginning of the 20th century, this great Russian scientist proposed the idea of \u200b\u200busing 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 with a variable mass. In his later writings, he presented a diagram of a 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 owns the idea of \u200b\u200bthe possibility of creating entire space cities in low-earth orbit. These are the discoveries that the scientist came to while studying jet propulsion in nature and technology. Rockets, as Tsiolkovsky showed, are the only vehicles that can overcome a Rocket, he defined as a mechanism that has a jet engine that uses the fuel and oxidizer on it. This apparatus 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 motion of bodies in nature and technology, moved on to practice. A large-scale task lay ahead of realizing an old dream of humanity. And a group of Soviet scientists, headed by Academician S.P.Korolev, coped with it. She implemented Tsiolkovsky's idea. The 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 was honored to be the first to fly in outer space. This important event for the world took place on April 12, 1961. Gagarin circled the entire globe on the Vostok satellite ship. 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 visit the lunar surface. He landed on it on July 20, 1969. In 1986, "Vega-1" and "Vega-2" (ships belonging to the USSR) examined Halley's comet at close range, which approaches the Sun only once every 76 years. Space exploration continues ...

As you can see, physics is a very important and useful science. Reactive motion in nature and technology is just one of the interesting issues that are discussed in it. And the achievements of this science are very, very significant.

How jet propulsion is used today in nature and technology

Particularly important discoveries have been made in physics in the past few centuries. While nature remains largely unchanged, technology is developing at a rapid pace. In our time, 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 the body could use to interact in order to change the modulus and direction of its speed. That is why only rockets can be used for flights 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 new discoveries.

Reactive motion in nature and technology

ABSTRACT IN PHYSICS

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

Reactive force arises without any interaction with external bodies.

The use of jet propulsion in nature

Many of us in our lives met with 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 use jet propulsion for movement. In addition, dragonfly larvae and some species of marine plankton move in this way. And often the efficiency of marine invertebrates when using jet propulsion is much higher than that of technological inventions.

Jet propulsion is used by many molluscs - octopuses, squid, cuttlefish. For example, a scallop clam moves forward due to the reactive force of a stream of water ejected from a shell when its valves are sharply compressed.

Octopus

Cuttlefish

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

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

Of greatest interest is the squid jet engine. The squid is the largest invertebrate inhabitant of the ocean depths. Squids have reached the highest perfection in jet navigation. In them, even the body with its external forms copies the rocket (or better to say - the rocket copies the squid, since it has an indisputable priority in this matter). When moving slowly, the squid uses a large diamond-shaped fin that bends periodically. He uses a jet engine for a quick throw. Muscle tissue - the mantle surrounds the body of the mollusk from all sides, the volume of its cavity is almost half the volume of the body of the squid. The animal sucks water into the mantle cavity, and then abruptly throws out a stream of water through a narrow nozzle and jerks back at high speed. In this case, all ten tentacles of the squid gather in a knot above the head, and it acquires a streamlined shape. The nozzle is equipped with a special valve, and the muscles can turn it, changing the direction of movement. The squid engine is very economical, it is capable of speeds up to 60 - 70 km / h. (Some researchers believe that even up to 150 km / h!) No wonder the squid is called a "live torpedo". Bending the tentacles folded in a bundle to the right, left, up or down, the squid turns in one direction or the other. Since such a rudder is very large in comparison with the animal itself, its slight movement is sufficient for the squid, even at full speed, to easily dodge a collision with an obstacle. A sharp turn of the steering wheel - and the swimmer rushes in the opposite direction. Now he bent the end of the funnel back and now slides head first. He bent it to the right - and a jet push threw him to the left. But when you need to swim fast, the funnel always sticks out right between the tentacles, and the squid rushes forward with its tail, like a crab would run - a runner endowed with the agility of a horse.

If there is no need to rush, squids and cuttlefish swim undulating with fins - miniature waves run along 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 time of the 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 range of flying squid. And such, it turns out, there are talents in the relatives of octopuses! The best mollusk pilot is the stenoteutis squid. English sailors call it - flying squid ("flying squid"). It is a small herring-sized animal. He pursues fish with such swiftness that he often jumps out of the water, sweeping like an arrow over its surface. He resorts to this trick and saving his life from predators - tuna and mackerel. Having developed the 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 live rocket flight lies so high above the water that flying squids often land 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 shellfish 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 yacht's bridge, which was almost seven meters above the water.

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

Octopuses can fly too. French naturalist Jean Verany saw an ordinary octopus speed up in an aquarium and suddenly jumped out of the water backwards. Having described an arc five meters long in the air, he flopped back into the aquarium. Gathering speed to jump, the octopus moved not only due to jet thrust, but also rowed with tentacles.
Baggy octopuses swim, of course, worse than squids, but at critical moments they can show a record class for the best sprinters. Employees at the California Aquarium tried to photograph an octopus attacking a crab. The octopus rushed to its prey so quickly that there was always lubricant on the film, even when shooting at the highest speeds. So the throw lasted hundredths of a second! Usually, octopuses swim relatively slowly. Joseph Seinle, who studied the migration of octopuses, calculated that an octopus half a meter in size floats on the sea at an average speed of about fifteen kilometers per hour. Each stream 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 propulsion can also be found in the plant world. For example, ripe fruits of "mad cucumber" at the slightest touch bounce off the stalk, and a sticky liquid with seeds is thrown out of the hole with force. At the same time, the cucumber itself flies 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 have several heavy stones, then by throwing stones in a certain direction, you will move 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 a recoil. If the weight of the bullet were equal to the weight of the gun, they would fly at the same speed. Recoil occurs because the rejected mass of gases creates a reactive force, thanks to which movement can be provided both in air and in airless space. And the greater the mass and velocity of the outflowing 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, mankind has dreamed of space travel. Science fiction writers have offered a variety of means to achieve this goal. In the 17th century, the story of the French writer Cyrano de Bergerac about the flight to the moon appeared. The hero of this story got to the moon in an iron cart, over which he constantly tossed a strong magnet. Pulling towards him, the wagon rose higher and higher above the Earth until it reached the moon. And Baron Munchausen said that he climbed to the moon on a bean stalk.

At the end of the first millennium AD, China invented jet propulsion, which propelled 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 designed for human flight was the Russian revolutionary N.I. Kibalchich. He was executed on April 3, 1881 for participating in the assassination attempt on Emperor Alexander II. He developed his project in prison after the death sentence. 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 belief supports me in my terrible situation ... I will calmly face death, knowing that my idea will not perish with me. "

The idea of \u200b\u200busing rockets for space flights was proposed at the beginning of this century by the Russian scientist Konstantin Eduardovich Tsiolkovsky. In 1903, an article by the teacher of the Kaluga gymnasium K.E. Tsiolkovsky "Exploration of world spaces with jet devices". 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. In the future, he developed a scheme for a rocket engine running on liquid fuel, proposed a multistage rocket design, and expressed the idea of \u200b\u200bthe possibility of creating entire space cities in near-earth orbit. He showed that the only device capable of overcoming gravity is a rocket, i.e. apparatus with a jet engine using fuel and an oxidizer located on the apparatus itself.