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Why do rockets take off in an arc? Why planes fly in an arc and not in a straight line - Hello world! — LiveJournal

You can now admire the takeoff of a space rocket on TV and in the movies. The rocket stands vertically on a concrete launch pad. At a command from the control center, the engines turn on, we see a flame igniting below, we hear a growing roar. And so the rocket, in a puff of smoke, takes off from the Earth and, at first slowly, and then faster and faster, rushes upward. A minute later she is already at such a height that planes cannot reach, and a minute later she is in Space, in the near-Earth airless space.

Rocket engines are called jet engines. Why? Because in such engines the traction force is a reaction force (counteraction) to the force that throws in the opposite direction a stream of hot gases obtained from the combustion of fuel in a special chamber. As you know, according to Newton's third law, the force of this reaction is equal to the force of action. That is, the force that lifts the rocket into outer space is equal to the force that is developed by the hot gases escaping from the rocket nozzle. If it seems incredible to you that gas, which is supposed to be ethereal, throws a heavy rocket into space orbit, remember that air compressed in rubber cylinders successfully supports not only a cyclist, but also heavy dump trucks. The white-hot gas escaping from the rocket nozzle is also full of strength and energy. So much so that after each rocket launch, the launch pad is repaired by adding concrete knocked out by the fire whirlwind.

Newton's third law can be formulated differently as the law of conservation of momentum. Momentum is the product of mass and velocity. In terms of the law of conservation of momentum, the launch of a rocket can be described as follows.

Initially, the momentum of the space rocket at rest on the launch pad was zero (the large mass of the rocket multiplied by its zero speed). But now the engine is on. The fuel burns, producing a huge amount of combustion gases. They have a high temperature and flow out of the rocket nozzle in one direction, downwards, at high speed. This creates a downward momentum vector whose magnitude is equal to the mass of the escaping gas multiplied by the velocity of that gas. However, due to the law of conservation of momentum, the total momentum of the space rocket relative to the launch pad should still be zero. Therefore, an upward impulse vector immediately arises, balancing the “rocket - ejected gases” system. How will this vector arise? Due to the fact that the rocket, which has been standing motionless until then, will begin to move upward. The upward momentum will be equal to the mass of the rocket multiplied by its speed.

If the rocket's engines are powerful, the rocket will very quickly gain enough speed to launch the spacecraft into low-Earth orbit. This speed is called the first escape velocity and is approximately 8 kilometers per second.

The power of a rocket engine is determined primarily by what fuel is burned in the rocket engines. The higher the combustion temperature of the fuel, the more powerful the engine. In the earliest Soviet rocket engines, the fuel was kerosene and the oxidizer was nitric acid. Now rockets use more active (and more poisonous) mixtures. The fuel in modern American rocket engines is a mixture of oxygen and hydrogen. The oxygen-hydrogen mixture is very explosive, but when burned it releases a huge amount of energy.

At what speed does a rocket fly into space?

  1. abstract science - creates illusions in the viewer
  2. If in low-Earth orbit, then 8 km per second.
    If outside, then 11 km per second. Like that.
  3. 33000 km/h
  4. Accurate - at a speed of 7.9 km/seconds, when leaving, it (the rocket) will rotate around the earth, if at a speed of 11 km/seconds, then this is already a parabola, i.e. it will eat a little further, there is a possibility that it may not return
  5. 3-5km/s, take into account the speed of rotation of the earth around the sun
  6. The spacecraft speed record (240 thousand km/h) was set by the American-German solar probe Helios-B, launched on January 15, 1976.

    The highest speed at which man has ever traveled (39,897 km/h) was achieved by the main module of Apollo 10 at an altitude of 121.9 km from the surface of the Earth when the expedition returned on May 26, 1969. On board the spacecraft were the crew commander, US Air Force Colonel (now Brigadier General) Thomas Patten Stafford (b. Weatherford, Oklahoma, USA, September 17, 1930), Captain 3rd Class, US Navy Eugene Andrew Cernan (b. Chicago, Illinois, USA, March 14, 1934 g.) and captain 3rd rank of the US Navy (now captain 1st rank retired) John Watte Young (b. San Francisco, California, USA, September 24, 1930).

    Of the women, the highest speed (28,115 km/h) was achieved by junior lieutenant of the USSR Air Force (now lieutenant colonel engineer, pilot-cosmonaut of the USSR) Valentina Vladimirovna Tereshkova (born March 6, 1937) on the Soviet spaceship Vostok 6 on June 16, 1963.

  7. 8 km/sec to overcome the Earth's gravity
  8. in a black hole you can accelerate to sublight speed
  9. Nonsense, thoughtlessly learned from school.
    8 or more precisely 7.9 km/s is the first cosmic speed - the speed of horizontal movement of a body directly above the surface of the Earth, at which the body does not fall, but remains a satellite of the Earth with a circular orbit at this very height, i.e. above the surface of the Earth ( and this does not take into account air resistance). Thus, PKS is an abstract quantity that connects the parameters of a cosmic body: radius and acceleration of free fall on the surface of the body, and has no practical significance. At an altitude of 1000 km, the speed of circular orbital motion will be different.

    The rocket increases speed gradually. For example, the Soyuz launch vehicle has a speed of 1.8 km/s 117.6 s after the launch at an altitude of 47.0 km, and 3.9 km/s at 286.4 s after the flight at an altitude of 171.4 km. After about 8.8 min. after launch at an altitude of 198.8 km, the spacecraft speed is 7.8 km/s.
    And the launch of the orbital vehicle into low-Earth orbit from the upper flight point of the launch vehicle is carried out by active maneuvering of the spacecraft itself. And its speed depends on the orbital parameters.

  10. This is all nonsense. It is not the speed that plays an important role, but the thrust force of the rocket. At an altitude of 35 km, full acceleration begins to PKS (first cosmic speed) up to 450 km altitude, gradually giving a course to the direction of the Earth's rotation. In this way, the altitude and traction force are maintained while overcoming the dense atmosphere. In a nutshell - there is no need to accelerate horizontal and vertical speeds at the same time; a significant deviation in the horizontal direction occurs at 70% of the desired height.
  11. which one
    a spaceship flies at altitude.

What pulls the projectile down

A passenger plane flies about two hundred and fifty kilometers in an hour. How far will a projectile flying ten times faster than an airplane fly in an hour?

It would seem that the projectile should fly about two and a half thousand kilometers in an hour.

In reality, however, the entire flight of the projectile lasts only about a minute, and the projectile usually flies no more than 15-20 kilometers.

What's the matter? What prevents a projectile from flying as long and as far as an airplane flies?

Rice. 96. How would a projectile fly when fired from a gun, the barrel of which is aimed directly at the target, and how should the barrel be directed so that the projectile hits the target

The plane flies for a long time because the propeller pulls it forward all the time. The screw works for many minutes, many hours in a row. Therefore, the plane can fly continuously for many hours in a row.

The projectile received a push in the gun channel, and then it flies on its own, no force anymore pushes it forward. From a mechanical point of view, a flying projectile will be a body moving in thirds and thirds. Such a body, teaches mechanics, must obey a very simple law: it must move rectilinearly and uniformly, unless no other force is applied to it.

Does the projectile obey this law, does it move in a straight line?

Rice. 97. A thrown stone describes an arc

Imagine that there is a target a kilometer away from you - for example, an enemy machine gun. Try to aim the 76-mm divisional cannon so that its barrel is pointed directly at the machine gun (Fig. 96), then fire a shot.

No matter how many times you shoot like this, you will never hit the target: each time the projectile will fall to the ground and explode, having flown only 300 meters. Continue the experiments, and you will soon come to the following conclusion: in order to hit, the barrel must be pointed in the wrong direction. target, and slightly higher than it (Fig. 96).

It turns out that the projectile does not fly straight forward: it descends in flight. What's the matter? Why does the projectile not fly straight? What force pulls the projectile down?

The answer is very simple: gravity forces the projectile to fall during flight.

Everyone knows that a thrown stone does not fly straight, but describes an arc and, after flying a short distance, falls to the ground or into the water (Fig. 97). All other things being equal, the stone flies farther, the harder it is thrown, the greater the speed it received at the moment of the throw.

Rice. 98. How would a projectile drop below the throwing line when firing in airless space?

Place a weapon in the place of the person throwing the stone, and replace the stone with a projectile; like any flying body, the projectile will be attracted to the ground during flight, and because of this it will move away from the line along which it was thrown; this line is called in artillery the “throwing line,” and the angle between this line and the horizon of the gun is the “throwing angle” (Fig. 98).

In the first second of flight, the projectile will fall approximately 5 meters (more precisely, 4.9 meters), in the second - almost 15 meters (more precisely, 14.7 meters), and in each subsequent second the falling speed will increase by almost 10 meters per second (more precisely, 9.8 meters per second). This is the law of free fall of bodies discovered by Galileo.

That is why the line of flight of the projectile - the trajectory - turns out not to be straight, but, just like for a thrown stone, similar to an arc.

Now try to answer this question: is there a connection between the throwing angle and the distance the projectile flies?

From the book Artillery author Vnukov Vladimir Pavlovich

Tracer projectile When you have to shoot at a target that is moving quickly - at an airplane or at a tank, it is useful to see the entire path of the projectile, its entire trajectory: this makes it easier to zero in. But a regular projectile is not visible during flight. That is why special projectiles were invented,

From the book Battle for the Stars-2. Space Confrontation (Part I) author Pervushin Anton Ivanovich

Chemical shell “In the morning of this clear spring day it was warm - a light southwest wind slightly moved the branches of the trees. Covered in front by the forest, a battery was hidden in the shallow growth. The camouflaged guns themselves seemed like bushes. At exactly six o'clock the battery heard

From the book Miracle Weapons of the USSR. Secrets of Soviet weapons [with illustrations] author Shirokorad Alexander Borisovich

Captain Shrapnel and his shell On August 7, 1914, there was a hot battle: the French fought with the Germans, who had just crossed the border and invaded France. Captain Lombal - commander of the French 75-mm cannon battery - examined the battlefield with binoculars. In the distance

From the book Rockets and Space Flights by Leigh Willie

Where is the projectile flying? Try firing from the same 76-mm cannon once with the barrel in a horizontal position, another time with a throwing angle of 3 degrees, and a third time with a throwing angle of 6 degrees. In the very first second of flight, the projectile, like us we already know

From the book Nanotechnology [Science, Innovation and Opportunity] by Foster Lynn

What slows down a projectile So, let's do the experiment. Let's load a 152-mm mortar with a charge that ejects a projectile with an initial speed of 171 meters per second. At a throwing angle of 20 degrees: according to calculations, the projectile should fly 1,900 meters. It will fly approximately this far

From the author's book

Which projectile flies further - light or heavy? But the secret of range is not only in the shape of the projectile. Let's fire projectiles of the same shape from three different guns. These guns are selected so that the initial speed of their shells is the same - 442 meters per second. The shells are almost

From the author's book

Why does a shell not fly at the same range at night as during the day? While the guns were being camouflaged at the firing position and trenches were being dug, the computers, having finished linking the firing position and the observation post, began work of a different kind: taking the book “Firing Tables”, they

From the author's book

Aircraft-projectile "M-44" Another project of Pavel Tsybin - the RSS cruise missile - was developed at OKB-23 by Vladimir Myasishchev. Here this device, which is essentially a prototype of a spaceplane, was carried out as a projectile aircraft "Izdeliye 44" ("M-44"). The unmanned aircraft "M-44"

Rockets rise into outer space by burning liquid or solid fuels. Once ignited in high-strength combustion chambers, these fuels, usually consisting of a fuel and an oxidizer, release enormous amounts of heat, creating very high pressure, which forces combustion products towards the earth's surface through expanding nozzles.

Since combustion products flow down from the nozzles, the rocket rises upward. This phenomenon is explained by Newton's third law, according to which for every action there is an equal and opposite reaction. Because liquid-fuel engines are easier to control than solid-fuel engines, they are commonly used in space rockets, such as the Saturn V rocket shown at left. This three-stage rocket burns thousands of tons of liquid hydrogen and oxygen to propel the spacecraft into orbit.

To rise quickly, the rocket's thrust must exceed its weight by about 30 percent. Moreover, if a spacecraft is to enter low-Earth orbit, it must reach a speed of about 8 kilometers per second. The thrust of rockets can reach several thousand tons.

  1. Five engines of the first stage lift the rocket to a height of 50-80 kilometers. After the first stage fuel is consumed, it will separate and the second stage engines will turn on.
  2. Approximately 12 minutes after launch, the second stage delivers the rocket to an altitude of more than 160 kilometers, after which it separates with empty tanks. The escape flare also detaches.
  3. Accelerated by a single third-stage engine, the rocket propels the Apollo spacecraft into a temporary low-Earth orbit at an altitude of about 320 kilometers. After a short break, the engines turn on again, increasing the spacecraft's speed to about 11 kilometers per second and pointing it towards the Moon.


The first stage F-1 engine burns fuel and releases combustion products into the environment.

After launching into orbit, the Apollo spacecraft receives an accelerating impulse towards the Moon. The third stage then separates and the spacecraft, consisting of the command and lunar modules, enters a 100-kilometer orbit around the Moon, after which the lunar module lands. Having delivered the astronauts who have visited the Moon to the command module, the lunar module separates and stops functioning.

If you fly often or often watch planes on services like , you've probably asked yourself questions about why the plane flies the way it does and not otherwise. What's the logic? Let's try to figure it out.

Why does a plane fly not in a straight line, but in an arc?

If you look at the flight path on the display in the cabin or on the computer at home, it does not look straight, but arched, curved towards the nearest pole (north in the northern hemisphere, south in the southern hemisphere). In fact, throughout almost the entire route (and the longer it is, the fairer it is) it tries to fly in a straight line. It’s just that the displays are flat, and the Earth is round, and the projection of a volumetric map onto a flat one modifies its proportions: the closer to the poles, the more curved the “arc” will be. This is very easy to check: take a globe and stretch a thread across its surface between two cities. This will be the shortest route. If you now transfer the line of the thread onto the paper, you will get an arc.

That is, the plane always flies in a straight line?

The plane does not fly as it pleases, but along air routes that are laid, of course, in such a way as to minimize the distance. The routes consist of segments between control points: they can be used as radio beacons, or simply coordinates on the map, which are assigned five-letter designations, most often easily pronounced and therefore memorable. Or rather, you need to pronounce them letter by letter, but, you see, remembering combinations like DOPIK or OKUDI is easier than GRDFT and UOIUA.

When plotting a route for each specific flight, various parameters are used, including the type of aircraft itself. So, for example, for twin-engine aircraft (and they are actively replacing three- and four-engine aircraft), ETOPS (Extended range twin engine operational performance standards) apply, which regulate route planning in such a way that the aircraft, crossing oceans, deserts or poles, is at the same time within a certain flight time to the nearest airfield capable of receiving this type of aircraft. Thanks to this, if one of the engines fails, it can be guaranteed to reach the emergency landing site. Different planes and airlines are certified for different flight times, it can be 60, 120 and even 180 and in rare cases 240 (!) minutes. Meanwhile, it is planned to certify the Airbus A350XWB for 350 minutes, and the Boeing 787 for 330; this would eliminate the need for four-engine aircraft even on routes like Sydney-Santiago (the world's longest commercial route over sea).

By what principle do planes move around the airport?

Firstly, it all depends on which runway is currently taking off from at the departure airport and which one is landing on at the arrival airport. If there are several options, then for each of them there are several exit and entry schemes: if you explain it in words, then the plane must proceed to each of the points of the scheme at a certain altitude at a certain (within limits) speed. The choice of runway depends on the current load of the airport, as well as, first of all, the wind. The fact is that both during takeoff and landing the wind must be headwind (or blow from the side, but still from the front): if the wind blows from behind, then the plane, in order to maintain the required speed relative to the air, will have to have too high a speed relative to the ground - maybe the strip is not long enough for take-off or braking. Therefore, depending on the direction of the wind, the plane moves either in one direction or in the other during takeoff and landing, and the runway has two takeoff and landing courses, which, rounded to tens of degrees, are used to designate the runway. For example, if the course is 90 in one direction, then in the other it will be 270, and the strip will be called “09/27”. If, as often happens at large airports, there are two parallel lanes, they are designated as left and right. For example, in Sheremetyevo 07L/25R and 07R/25L, respectively, and in Pulkovo – 10L/28R and 10R/28L.

At some airports, the runways only work in one direction - for example, in Sochi there are mountains on one side, so you can only take off towards the sea and land only from the sea: in any direction the wind will blow from behind either during take-off or landing, so the pilots are guaranteed to experience a little extreme.

Flight patterns in the airport area take into account numerous restrictions - for example, a ban on aircraft flying directly over cities or special zones: these can be either sensitive facilities or the banal cottage villages of Rublyovka, whose residents do not really like the noise overhead.

Why does a plane fly faster in one direction than in the other?

This is a “holiday” question - perhaps more copies have been broken only around the problem with an airplane standing on a moving belt - “whether it will take off or not.” Indeed, the plane flies faster to the east than to the west, and if you get from Moscow to Los Angeles in 13 hours, then you can get back in 12.

That is, it is faster to fly from west to east than from east to west.

The humanist thinks that the Earth is spinning, and when you fly in one direction, the destination gets closer, because the planet manages to turn under you.

If you hear such an explanation, urgently give the person a geography textbook for the sixth grade, where they will explain to him that, firstly, the Earth rotates from west to east (i.e., according to this theory, everything should be the other way around), and secondly, the atmosphere rotates with the Earth. Otherwise, you could take off in a hot air balloon and hang in place, waiting to be turned around to where you need to land: free travel!

The technician is trying to explain this phenomenon by the Coriolis force, which acts on the plane in the non-inertial reference frame “Earth-plane”: when moving in one direction, its weight becomes greater, and in the other, accordingly, less. The only trouble is that the difference in the weight of the aircraft created by the Coriolis force is very small even compared to the mass of the payload on board. But that’s not so bad: since when does mass affect speed? You can drive a car at 100 km/h, either alone or with five people. The only difference will be in fuel consumption.

The real reason that a plane flies faster to the east than to the west is that winds at an altitude of several kilometers most often blow from west to east, and so in one direction the wind turns out to be tailwind, increasing the speed relative to the Earth, and in the other - oncoming, slowing down. Why do the winds blow this way? Ask Coriolis, for example. By the way, the study of high-altitude jet streams (these are strong winds in the form of relatively narrow air currents in certain zones of the atmosphere) makes it possible to plot routes in such a way that, once “in the jet,” you can maximize speed and save fuel.