Interesting information about jet propulsion. Jet propulsion in nature - presentation Using jet propulsion

Today, most people associate jet propulsion primarily, of course, with the latest scientific and technical developments. From textbooks on physics, we know that by "reactive" they mean the movement that occurs as a result of separation from an object (body) of any of its parts. A man wanted to rise into the sky to the stars, he strove to fly, but he could fulfill his dream only with the advent of jet aircraft and stepped spacecraft capable of traveling great distances, accelerating to supersonic speeds, thanks to modern jet engines installed on them. Designers and engineers developed the possibility of using jet propulsion in engines. Fantasts also did not stand aside, offering the most incredible ideas and ways to achieve this goal. Surprisingly, this principle of movement is widespread in wildlife. It is enough to look around, you can notice the inhabitants of the seas and land, among which there are plants, the basis of which is the reactive principle.

Story

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 a reactive method practical use. They were the first, taking as a basis the method of movement of cuttlefish and octopuses, back in the 13th century they invented rockets. They were used in fireworks, making a big impression, and also as flares, there may have been live rockets that were used as rocket artillery. Over time, this technology came to Europe.

N. Kibalchich became the discoverer of the new time, having invented a scheme for a prototype aircraft with a jet engine. He was an outstanding inventor and a convinced revolutionary, for which he was in prison. It was while in prison that he made history by creating his project. After his execution for active revolutionary activity and speaking out against the monarchy, his invention was forgotten on the archive shelves. Some time later, K. Tsiolkovsky was able to improve the ideas of Kibalchich, proving the possibility of exploring outer space through the jet movement of spacecraft.

Later, during the Great Patriotic War, the famous Katyushas, field rocket artillery systems, appeared. So the affectionate name of the people unofficially referred to the powerful installations that were used by the forces of the USSR. 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, however, called this combat rocket launcher "Stalin's organ" for appearance, which resembled a musical instrument and a piercing 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, petiolate garlic, heart touchy, double-cut pikulnik, three-veined mehringia.

Prickly, otherwise mad cucumber, belongs to the gourd family. This plant reaches a large size, has a thick root with a rough stem and large leaves. It grows in the territory of Central Asia, the Mediterranean, the Caucasus, is quite common in the south of Russia and Ukraine. Inside the fruit, during the ripening period, the seeds are 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 fly out of the fruit at a speed of 10 m/s. Due to the ability to shoot at 12 m in length, the plant was called the "lady's gun".

The heart of the touchy is an annual widespread species. It is found, as a rule, in shady forests, along the banks along rivers. Arriving in the northeast North America and to South Africa, successfully took root. The touchy heart is propagated by seeds. The seeds at the touchy core are small, weighing no more than 5 mg, which are thrown to a distance of 90 cm. Thanks to this method of seed distribution, the plant got its name.

Animal world

Jet propulsion — Interesting Facts relating to the animal world. In cephalopods, reactive movement occurs through water exhaled through a siphon, which usually narrows to a small opening to obtain maximum exhalation velocity. Water passes through the gills before exhalation, fulfilling the dual purpose of respiration and locomotion. Sea hares, otherwise gastropods, use similar means of locomotion, but without the complex neurological apparatus of cephalopods, they move more clumsily.

Some knightfish have also evolved jet propulsion by passing water over their gills to supplement their fin propulsion.

In dragonfly larvae, reactive power 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 jet displacement. Thanks to him, the scallops can float up and move to long distance using the shell opening-closing technique.

The squid also uses this method, absorbing water, and then pushing it through the funnel with great force, it 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 designed a water cannon. The 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 squids, salps use the most efficient engines, spending an order of magnitude less energy than squids. When moving, the salpa launches water into the hole in front, and then enters a wide cavity where the gills are stretched. After a sip, the hole closes, and with the help of contracting longitudinal and transverse muscles that compress the body, water is ejected through the hole from behind.

The most unusual of all the mechanisms of movement boasts an ordinary cat. Marcel Desprez suggested that the body is able to move and change its position even with the help of internal forces alone (without repelling or relying on anything), from which it could be concluded that Newton's laws could be wrong. The proof of his assumption could serve as a cat that fell from a height. During the fall upside down, she will still land on all her paws, this has already become a kind of axiom. Having photographed in detail the movement of the cat, we were able to see everything that she was doing in the air frame by frame. We saw her movement with her paw, which caused a response of the body, turning in the opposite direction relative to the movement of the paw. Acting according to Newton's laws, the cat landed successfully.

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

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

Jet propulsion in nature.

Completed by a student:

10 "A" class

Kaklyugina Ekaterina.

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

Many of us in our lives 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 also use jet propulsion to move around. In addition, this is how dragonfly larvae and some types of marine plankton move. And often the efficiency of marine invertebrates when using jet propulsion is much higher than that of techno 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 jet of water ejected from the shell during a sharp compression of its valves.

The cuttlefish, like most cephalopods, moves in the water in the following way. She takes water into the gill cavity through a lateral slit and a special funnel in front of the body, and then vigorously throws 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 motion can also be found in the plant world. For example, the ripened fruits of the “mad cucumber” at the slightest touch bounce off the stalk, and a sticky liquid with seeds is ejected with force from the hole formed. 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 you have some heavy rocks, then throwing rocks in a certain direction will move you in the opposite direction. The same will happen in outer space, but they use jet engines.

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 discarded mass of gases creates a reactive force, due to which movement can be ensured both in air and in airless space. And the greater the mass and speed of the outflowing gases, the greater the recoil force felt by our shoulder, the stronger the reaction of the gun, the greater the reactive force.

The use of jet propulsion in technology.

For many centuries, mankind has dreamed of space flights. Science fiction writers have proposed a variety of means to achieve this goal. In the 17th century, a story appeared by the French writer Cyrano de Bergerac about a flight to the moon. The hero of this story got to the moon in an iron wagon, over which he constantly threw a strong magnet. Attracted to 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 the stalk of a bean.

At the end of the first millennium AD, China invented jet propulsion that 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 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 position ... 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 our century by the Russian scientist Konstantin Eduardovich Tsiolkovsky. In 1903, an article by a teacher of the Kaluga gymnasium K.E. Tsiolkovsky "Research of world spaces by 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. Subsequently, he developed a scheme 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 near-Earth orbit. He showed that the only apparatus capable of overcoming gravity is a rocket, i.e. an apparatus with a jet engine using fuel and an oxidizer located on the apparatus itself.

For most people, the term "jet propulsion" is presented as modern progress in science and technology, especially in the field of physics. Jet propulsion in technology is associated by many with spacecraft, satellites and jet aircraft. It turns out that the phenomenon of jet propulsion existed much earlier than man 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 the 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 appears that moves the body in the opposite direction from the direction of movement, separating a part from it. Every time when matter breaks out of an object, and the object moves into reverse direction, reactive motion is observed. In order 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 takeoff: the 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 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 mechanics of gravity and tell us what happens when things move. They especially clearly explain the movement of bodies in space.

Newton's second law determines that the strength 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 release a large number of high speed energy. Newton's third law says 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 of action is the matter that flies out of the exhaust pipe. The reaction is to push the rocket forward. It is the force of emissions from it that pushes the rocket. In space, where a rocket has little to no weight, even a small push from the rocket engines can make a large ship fly forward quickly.

Jet propulsion technology

The physics of jet motion is that the acceleration or deceleration of the 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:

the phenomenon of recoil from a shot;
explosions;
blows during accidents;
recoil when using a powerful hose;
a boat with a jet engine;
jet plane and rocket.

Bodies create 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 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 momentum. 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 within the system changes due to their mutual influence. The total momentum of bodies in a closed system remains unchanged for various movements and interactions of bodies. This is the law of conservation of momentum.

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

The law of conservation of momentum has a wide practical application. It allows you to explain the jet propulsion, due to which top speeds.

Jet propulsion 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 to release the gas that occurs during the combustion of fuel. Under the action of high temperature and pressure, the gas exits the engine nozzle at great speed. Before the launch of a rocket, its momentum relative to the Earth is zero. At the moment of launch, the rocket also receives a momentum that is equal to the momentum of the gas, but opposite in direction.

An example of jet propulsion physics can be seen everywhere. During the celebration of a birthday, a balloon may well become a rocket. How? Inflate the balloon by pinching the open hole to prevent air from escaping. Now release it. Balloon with great speed 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 BC, when Heron of Alexandria designed the first jet engine, the aeolipil. 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 successfully used Heron's engine to open and close the doors of the temple. Modification of the eolipil - Segner's wheel, which is effectively used in our time for irrigation of agricultural land. In the 16th century, Giovanni 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 to move on the ground date back to the 15-17th centuries. Even 1000 years ago, the Chinese had rockets that they used as a military weapon. 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. Rocket studies of past centuries were taken as the basis, which described in detail the use of powder boosters, which can significantly reduce the length of the afterburner and takeoff 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 at the end of the 19th century.

The first jet engines

For the first time, the development of a jet engine in Russia was taken up at the beginning of the 20th century. The theory of the movement of jet vehicles and rocket technology 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, operating with the help of a jet turbine. The first jet aircraft were created by German engineers. Design and production were carried out secretly in camouflaged factories. Hitler, with his idea of becoming a world ruler, connected the best German designers 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, freely took to the air 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.
Max speed aircraft reached 900 km / h.

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

Prototypes of modern airliners

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

The I-250, better known as the legendary MiG-13, is a fighter developed by A. I. Mikoyan. 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, for the first time, a Sukhoi Su-5 jet aircraft took to the skies, rising and flying due to an air-jet motor-compressor and piston engine located in the tail section of the structure.

After the end of the war and the surrender of Nazi Germany Soviet Union as trophies went to German aircraft with jet engines JUMO-004 and BMW-003.

First world prototypes

Not only German and Soviet designers were engaged in the development, testing of new airliners and their production. Engineers from the USA, Italy, Japan, Great Britain also created a lot of successful projects applied jet propulsion in engineering. Among the first developments with various types of engines include:

Non-178 - German aircraft with a turbojet power plant, took off in August 1939.
GlosterE. 28/39 - an aircraft originally from the UK, with a turbojet type engine, first took to the skies in 1941.
Not-176 - a fighter, 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 power plant.
Campini N.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, the so-called disposable aircraft with a kamikaze pilot on board.

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

The GlosterMeteor, an air-breathing fighter aircraft manufactured in Great Britain in 1943, played a significant role in the Second World War, and after its completion, it performed the task of intercepting German V-1 missiles.
The Lockheed F-80 is a jet aircraft manufactured in the USA using an AllisonJ type engine. These aircraft participated in the Japanese-Korean war more than once.
The B-45 Tornado is a prototype of the modern American B-52 bombers, created in 1947.
MiG-15 - a follower of the recognized MiG-9 jet fighter, which actively participated in the military conflict in Korea, was produced in December 1947.
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 on supersonic speeds. Now there are liners capable of accommodating a large number of passengers and cargo, of enormous size and unimaginable speed of over 3,000 km / h, military aircraft equipped with modern combat equipment.

But among this variety there are several designs of jet record holders:

The Airbus A380 is the most spacious aircraft capable of accommodating 853 passengers on board, which is ensured by a two-deck design. He is also one of the most luxurious and expensive airliners of our time. The largest passenger airliner in the air.
Boeing 747 - for over 35 years it was considered the most spacious double-decker airliner and could carry 524 passengers.
AN-225 "Mriya" is a cargo aircraft that boasts a payload capacity of 250 tons.
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 a rapidly developing modern aviation. Now several Western and Russian manned, passenger, unmanned airliners with jet engines are being designed, the release of which is scheduled for the next few years.

The Russian innovative developments of the future include the 5th generation fighter PAK FA - T-50, the first copies of which will enter 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 suggested by nature itself. Its action is used by the larvae of some species of dragonflies, jellyfish, many mollusks - scallops, cuttlefish, octopuses, squids. They apply a kind of "repulsion principle". Cuttlefish draw in water and throw it out so quickly that they themselves make a leap forward. Squid 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 with the help of 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 ejection of the jet. Water is drawn in by an engine running on diesel or gasoline.

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

Manifestation in nature and technology of jet propulsion 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 space, and jet propulsion is a prime example of this.

Multitons soar into the sky spaceships, and transparent, gelatinous jellyfish, cuttlefish and octopuses deftly maneuver in sea waters - what do they have in common? It turns out that in both cases, the principle of jet propulsion is used to move. It is this topic that our today's article is devoted to.

Let's look into history

Most The first reliable information about rockets dates back to the 13th century. They were used by Indians, Chinese, Arabs and Europeans in combat operations as military and signal weapons. Then followed centuries of almost complete oblivion of these devices.

In Russia, the idea of using a jet engine was revived thanks to the work of the Narodnaya Volya revolutionary Nikolai Kibalchich. Sitting in the royal dungeons, he developed Russian project jet engine and aircraft for people. Kibalchich was executed, and for many years his project was gathering dust in the archives of the tsarist secret police.

The main ideas, drawings and calculations of this talented and courageous person were further developed in the works of K. E. Tsiolkovsky, who proposed using them for interplanetary communications. From 1903 to 1914, he published a number of works, where he convincingly proves the possibility of using jet propulsion to explore outer space and substantiates the feasibility of using multi-stage rockets.

Many scientific developments of Tsiolkovsky are still used in rocket science.

biological missiles

How did it come about the idea of moving by pushing off your own jet stream? Perhaps, closely watching the marine life, the inhabitants of the coastal zones noticed how this happens in the animal world.

For example, scallop moves due to the reactive force of the water jet ejected from the shell during the rapid compression of its valves. But he will never keep up with the fastest swimmers - squids.

Their rocket-shaped bodies rush tail forward, throwing out stored water from a special funnel. move according to the same principle, squeezing out water by contracting their transparent dome.

Nature endowed a "jet engine" and a plant called "squirting cucumber". When its fruits are fully ripe, in response to the slightest touch, it shoots out gluten with seeds. The fetus itself is thrown in the opposite direction at a distance of up to 12 m!

Neither marine life nor plants know the physical laws underlying this mode of locomotion. We'll try to figure this out.

Physical foundations of the principle of jet propulsion

Let's start with a simple experiment. Inflate a rubber ball and, without tying, we will let go into free flight. The rapid movement of the ball will continue as long as the stream of air flowing from it is strong enough.

To explain the results of this experience, we should turn to the third law, which states that two bodies interact with forces equal in magnitude and opposite in direction. Therefore, the force with which the ball acts on the jets of air escaping from it is equal to the force with which the air repels the ball from itself.

Let's transfer this reasoning to the rocket. These devices at great speed throw out some of their mass, as a result of which they themselves receive acceleration in the opposite direction.

From a physics point of view, this the process is clearly explained by the law of conservation of momentum. Momentum is the product of the body's mass and its velocity (mv) While the rocket is at rest, its velocity and momentum are zero. If a jet stream is ejected from it, then the remaining part, according to the law of conservation of momentum, must acquire such a speed that the total momentum is still equal to zero.

Let's look at the formulas:

m g v g + m p v p =0;

m g v g \u003d - m p v p,

where m g v g the momentum created by the jet of gases, m p v p the momentum received by the rocket.

The minus sign shows that the direction of movement of the rocket and the jet stream are opposite.

The device and principle of operation of a jet engine

In technology, jet engines propel aircraft, rockets, and put spacecraft into orbit. Depending on the purpose, they have a different device. But each of them has a supply of fuel, a chamber for its combustion and a nozzle that accelerates the jet stream.

The interplanetary automatic stations are also equipped with an instrument compartment and cabins with a life support system for astronauts.

Modern space rockets These are complex, multi-stage aircraft using latest achievements engineering thought. After launch, the fuel in the lower stage burns first, after which it separates from the rocket, reducing its total mass and increasing its speed.

Then the fuel is consumed in the second stage, and so on. Finally, the aircraft is brought to a given trajectory and begins its independent flight.

Let's dream a little

The great dreamer and scientist K. E. Tsiolkovsky gave future generations the confidence that jet engines will allow humanity to break out of the earth's atmosphere and rush into space. His prediction came true. The moon, and even distant comets, are successfully explored by spacecraft.

In astronautics, liquid propellant engines are used. Using petroleum products as fuel, but the speeds that can be obtained with their help are insufficient for very long flights.

Perhaps you, our dear readers, will witness the flights of earthlings to other galaxies on vehicles with nuclear, thermonuclear or ion jet engines.

If this message was useful to you, I would be glad to see you

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Application of jet propulsion in nature

Many of us in our lives have met while swimming in the sea with jellyfish. But few people thought that jellyfish also use jet propulsion to move around. And often the efficiency of marine invertebrates when using jet propulsion is much higher than that of technical inventions.

slide 3

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

slide 4

Cuttlefish

slide 5

Squid

Squids have reached the highest level of excellence in jet navigation. They even have a body that copies a rocket with its external forms (or better, a rocket copies a squid, since it has an indisputable priority in this matter)

slide 6

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 great force through a special hole - a "funnel", and at high speed (about 70 km / h) moves back in jolts. In this case, all ten tentacles of the squid are collected in a knot above the head and it acquires a streamlined shape.

Slide 7

flying squid

This is a small animal the size of a herring. He pursues fish with such swiftness that he often jumps out of the water, rushing 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 the flight of a living rocket lies so high above the water that flying squids often fall on the decks of ocean-going ships. Four or 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. The French naturalist Jean Verany saw an ordinary octopus speed up in an aquarium and suddenly jump out of the water backwards. Describing in the air an arc about five meters long, he plopped back into the aquarium. Gaining speed for the jump, the octopus moved not only due to jet thrust, but also rowed with tentacles.