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1 first escape velocity = 7899.9999999999 meters per second [m/s]

Initial value

Converted value

meter per second meter per hour meter per minute kilometer per hour kilometer per minute kilometers per second centimeter per hour centimeter per minute centimeter per second millimeter per hour millimeter per minute millimeter per second foot per hour foot per minute foot per second yard per hour yard per minute yard per second mile per hour mile per minute mile per second knot knot (Brit.) speed of light in vacuum first space velocity second space velocity third space velocity earth's rotation speed sound speed in fresh water sound speed in sea water (20°C, depth 10 meters) Mach number (20°C, 1 atm) Mach number (SI standard)

Thermal efficiency and fuel efficiency

More about speed

General information

Speed ​​is a measure of the distance traveled in a given time. Velocity can be a scalar quantity or a vector value - the direction of motion is taken into account. The speed of movement in a straight line is called linear, and in a circle - angular.

Speed ​​measurement

average speed v find by dividing the total distance traveled ∆ x for the total time ∆ t: v = ∆x/∆t.

In the SI system, speed is measured in meters per second. Kilometers per hour in the metric system and miles per hour in the US and UK are also widely used. When, in addition to the magnitude, the direction is also indicated, for example, 10 meters per second to the north, then we are talking about vector speed.

The speed of bodies moving with acceleration can be found using the formulas:

• a, with initial speed u during the period ∆ t, has a final speed v = u + a×∆ t.
• A body moving with constant acceleration a, with initial speed u and final speed v, has an average speed ∆ v = (u + v)/2.

Average speeds

The speed of light and sound

According to the theory of relativity, the speed of light in a vacuum is the highest speed at which energy and information can travel. It is denoted by the constant c and equal to c= 299,792,458 meters per second. Matter cannot move at the speed of light because it would require an infinite amount of energy, which is impossible.

The speed of sound is usually measured in an elastic medium and is 343.2 meters per second in dry air at 20°C. The speed of sound is lowest in gases and highest in solids. It depends on the density, elasticity, and shear modulus of the substance (which indicates the degree of deformation of the substance under shear loading). Mach number M is the ratio of the speed of a body in a liquid or gas medium to the speed of sound in this medium. It can be calculated using the formula:

M = v/a,

where a is the speed of sound in the medium, and v is the speed of the body. The Mach number is commonly used in determining speeds close to the speed of sound, such as aircraft speeds. This value is not constant; it depends on the state of the medium, which, in turn, depends on pressure and temperature. Supersonic speed - speed exceeding 1 Mach.

Vehicle speed

Below are some vehicle speeds.

• Passenger aircraft with turbofan engines: the cruising speed of passenger aircraft is from 244 to 257 meters per second, which corresponds to 878–926 kilometers per hour or M = 0.83–0.87.
• High-speed trains (like the Shinkansen in Japan): These trains reach top speeds of 36 to 122 meters per second, i.e. 130 to 440 kilometers per hour.

animal speed

The maximum speeds of some animals are approximately equal:

human speed

• Humans walk at about 1.4 meters per second, or 5 kilometers per hour, and run at up to about 8.3 meters per second, or 30 kilometers per hour.

Examples of different speeds

four dimensional speed

In classical mechanics, the vector velocity is measured in three-dimensional space. According to the special theory of relativity, space is four-dimensional, and the fourth dimension, space-time, is also taken into account in the measurement of speed. This speed is called four-dimensional speed. Its direction may change, but the magnitude is constant and equal to c, which is the speed of light. Four-dimensional speed is defined as

U = ∂x/∂τ,

where x represents the world line - a curve in space-time along which the body moves, and τ - "proper time", equal to the interval along the world line.

group speed

Group velocity is the velocity of wave propagation, which describes the propagation velocity of a group of waves and determines the rate of wave energy transfer. It can be calculated as ∂ ω /∂k, where k is the wave number, and ω - angular frequency. K measured in radians / meter, and the scalar frequency of wave oscillations ω - in radians per second.

Hypersonic speed

Hypersonic speed is a speed exceeding 3000 meters per second, that is, many times higher than the speed of sound. Solid bodies moving at such a speed acquire the properties of liquids, because due to inertia, the loads in this state are stronger than the forces holding the molecules of a substance together during a collision with other bodies. At ultra-high hypersonic speeds, two colliding solid bodies turn into gas. In space, bodies move at precisely this speed, and engineers designing spacecraft, orbital stations, and spacesuits must take into account the possibility of a station or astronaut colliding with space debris and other objects when working in outer space. In such a collision, the skin of the spacecraft and the suit suffer. Equipment designers are conducting hypersonic collision experiments in special laboratories to determine how strong impact suits can withstand, as well as skins and other parts of the spacecraft, such as fuel tanks and solar panels, testing them for strength. To do this, spacesuits and skin are subjected to impacts by various objects from a special installation with supersonic speeds exceeding 7500 meters per second.

Our planet. In this case, the object will move unevenly and unevenly accelerated. This is because the acceleration and speed in this case will not satisfy the conditions with a constant speed/acceleration in direction and magnitude. These two vectors (velocity and acceleration) as they move along the orbit will change their direction all the time. Therefore, such a motion is sometimes called motion at a constant speed along a circular orbit.

The first cosmic is the speed that must be given to the body in order to bring it into a circular orbit. At the same time, it will become similar. In other words, the first cosmic one is the speed, reaching which a body moving above the Earth's surface will not fall on it, but will continue to orbit.

For the convenience of calculations, this motion can be considered as occurring in a non-inertial frame of reference. Then the body in orbit can be considered to be at rest, since two and gravity will act on it. Therefore, the first will be calculated by considering the equality of these two forces.

It is calculated according to a certain formula, which takes into account the mass of the planet, the mass of the body, the gravitational constant. Substituting the known values ​​into a certain formula, they get: the first cosmic speed is 7.9 kilometers per second.

In addition to the first space speed, there are second and third speeds. Each of the cosmic velocities is calculated according to certain formulas and is physically interpreted as the speed at which any body launched from the surface of the planet Earth becomes either an artificial satellite (this will happen when the first cosmic speed is reached) or leaves the Earth's gravitational field (this happens when second cosmic velocity), or leave the solar system, overcoming the attraction of the Sun (this happens at the third cosmic velocity).

Having gained a speed equal to 11.18 kilometers per second (the second space), it can fly towards the planets in the solar system: Venus, Mars, Mercury, Saturn, Jupiter, Neptune, Uranus. But to reach any of them, you need to take into account their movement.

Previously, scientists believed that the movement of the planets is uniform and occurs in a circle. And only I. Kepler established the true form of their orbits and the pattern by which the speeds of movement of celestial bodies change as they rotate around the Sun.

The concept of cosmic velocity (first, second or third) is used when calculating the movement of an artificial body in any planet or its natural satellite, as well as the Sun. This way you can determine the cosmic speed, for example, for the Moon, Venus, Mercury and other celestial bodies. These velocities must be calculated using formulas that take into account the mass of the celestial body, the force of gravity of which must be overcome

The third cosmic one can be determined based on the condition that the spacecraft must have a parabolic trajectory of motion relative to the Sun. To do this, during launch near the surface of the Earth and at an altitude of about two hundred kilometers, its speed should be approximately 16.6 kilometers per second.

Accordingly, cosmic velocities can also be calculated for the surfaces of other planets and their satellites. So, for example, for the Moon, the first space will be 1.68 kilometers per second, the second - 2.38 kilometers per second. The second space velocity for Mars and Venus, respectively, is 5.0 kilometers per second and 10.4 kilometers per second.

If a certain body is given a speed equal to the first cosmic velocity, then it will not fall to the Earth, but will become an artificial satellite moving in a near-Earth circular orbit. Recall that this speed should be perpendicular to the direction to the center of the Earth and equal in magnitude
v I = √(gR) = 7.9 km/s,
where g \u003d 9.8 m / s 2− free fall acceleration of bodies near the Earth's surface, R = 6.4 × 10 6 m− radius of the Earth.

Can a body completely break the chains of gravity that “bind” it to the Earth? It turns out that it can, but for this it needs to be “thrown” with even greater speed. The minimum initial speed that must be reported to the body at the surface of the Earth in order for it to overcome the earth's gravity is called the second cosmic velocity. Let's find its meaning vII.
When the body moves away from the Earth, the force of attraction does negative work, as a result of which the kinetic energy of the body decreases. At the same time, the force of attraction also decreases. If the kinetic energy falls to zero before the force of attraction becomes zero, the body will return back to Earth. To prevent this from happening, it is necessary that the kinetic energy be kept non-zero until the force of attraction vanishes. And this can happen only at an infinitely large distance from the Earth.
According to the kinetic energy theorem, the change in the kinetic energy of a body is equal to the work done by the force acting on the body. For our case, we can write:
0 − mv II 2 /2 = A,
or
mv II 2 /2 = −A,
where m is the mass of the body thrown from the Earth, A− work of the force of attraction.
Thus, to calculate the second cosmic velocity, it is necessary to find the work of the force of attraction of the body to the Earth when the body moves away from the surface of the Earth to an infinitely large distance. Surprising as it may seem, this work is not at all infinitely large, despite the fact that the movement of the body seems to be infinitely large. The reason for this is the decrease in the force of attraction as the body moves away from the Earth. What is the work done by the force of attraction?
Let us use the feature that the work of the gravitational force does not depend on the shape of the trajectory of the body, and consider the simplest case - the body moves away from the Earth along a line passing through the center of the Earth. The figure shown here shows the globe and a body of mass m, which moves along the direction indicated by the arrow.

Find a job first A 1, which makes the force of attraction in a very small area from an arbitrary point N to the point N 1. The distances of these points to the center of the Earth will be denoted by r and r1, respectively, so work A 1 will be equal to
A 1 = -F(r 1 - r) = F(r - r 1).
But what is the meaning of strength F should be substituted into this formula? Because it changes from point to point: N it is equal to GmM/r 2 (M is the mass of the Earth), at the point N 1 − GmM/r 1 2.
Obviously, you need to take the average value of this force. Since the distances r and r1, differ little from each other, then as the average we can take the value of the force at some midpoint, for example, such that
r cp 2 = rr 1.
Then we get
A 1 = GmM(r − r 1)/(rr 1) = GmM(1/r 1 − 1/r).
Arguing in the same way, we find that on the segment N 1 N 2 work is done
A 2 = GmM(1/r 2 − 1/r 1),
Location on N 2 N 3 work is
A 3 = GmM(1/r 3 − 1/r 2),
and on the site NN 3 work is
A 1 + A 2 + A 2 = GmM(1/r 3 − 1/r).
The pattern is clear: the work of the force of attraction when moving a body from one point to another is determined by the difference in the reciprocal distances from these points to the center of the Earth. Now it's easy to find and all the work BUT when moving a body from the surface of the Earth ( r = R) over an infinite distance ( r → ∞, 1/r = 0):
A = GmM(0 − 1/R) = −GmM/R.
As can be seen, this work is indeed not infinitely large.
Substituting the resulting expression for BUT into the formula
mv II 2 /2 = −GmM/R,
find the value of the second cosmic velocity:
v II = √(−2A/m) = √(2GM/R) = √(2gR) = 11.2 km/s.
This shows that the second cosmic velocity in √{2} times greater than the first cosmic velocity:
vII = √(2)vI.
In our calculations, we did not take into account the fact that our body interacts not only with the Earth, but also with other space objects. And first of all - with the Sun. Having received the initial speed equal to vII, the body will be able to overcome gravity towards the Earth, but will not become truly free, but will turn into a satellite of the Sun. However, if the body near the surface of the Earth is informed of the so-called third cosmic velocity v III = 16.6 km/s, then it will be able to overcome the force of attraction to the Sun.
See example

02.12.2014

Lesson 22 (Grade 10)

Subject. Artificial satellites of the Earth. development of astronautics.

About the movement of thrown bodies

In 1638, Galileo's book "Conversations and Mathematical Proofs Concerning Two New Branches of Science" was published in Leiden. The fourth chapter of this book was called "On the motion of thrown bodies." Not without difficulty, he managed to convince people that in an airless space "a grain of lead should fall with the same speed as a cannonball." But when Galileo told the world that a cannonball that had flown out of a cannon in a horizontal direction had been in flight for the same amount of time as a cannonball that had simply fallen out of its muzzle to the ground, they did not believe him. Meanwhile, this is true: a body thrown from a certain height in a horizontal direction moves to the ground in the same time as if it had simply fallen vertically downward from the same height.
To verify this, we will use the device, the principle of operation of which is illustrated in Figure 104, a. After being hit with a hammer M on elastic plate P the balls begin to fall and, despite the difference in trajectories, simultaneously reach the ground. Figure 104b shows a stroboscopic photograph of falling balls. To obtain this photograph, the experiment was carried out in the dark, and the balls were illuminated at regular intervals with a bright flash of light. At the same time, the camera shutter was open until the balls fell to the ground. We see that at the same moments of time when the flashes of light occurred, both balls were at the same height and just as simultaneously they reached the ground.

Free fall time h(near the surface of the Earth) can be found by the formula known from mechanics s=at2/2. Replacing here s on the h and a on the g, we rewrite this formula in the form

whence, after simple transformations, we obtain

The same time will be in flight and the body thrown from the same height in the horizontal direction. In this case, according to Galileo, “to the uniform unimpeded motion, another one is added, caused by the force of gravity, due to which a complex motion arises, consisting of uniform horizontal and naturally accelerated motions.”
During the time determined by expression (44.1), moving in a horizontal direction with a speed v0(i.e., with the speed with which it was thrown), the body will move horizontally a distance

From this formula it follows that the flight range of a body thrown in a horizontal direction is proportional to the initial speed of the body and increases with the height of the throw.
To find out which trajectory the body moves in this case, let us turn to experiment. We attach a rubber tube equipped with a tip to the water tap and direct the stream of water in a horizontal direction. In this case, the water particles will move in exactly the same way as a body thrown in the same direction. Turning off or, conversely, turning the tap, you can change the initial speed of the jet and thus the range of flight of water particles (Fig. 105), however, in all cases, the water jet will have the form parabolas. To verify this, a screen with parabolas pre-drawn on it should be placed behind the jet. The water jet will exactly match the lines shown on the screen.

So, a freely falling body with a horizontal initial velocity moves along a parabolic trajectory.
By parabola the body will also move when it is thrown at some acute angle to the horizon. The flight range in this case will depend not only on the initial speed, but also on the angle at which it was directed. Conducting experiments with a jet of water, it can be established that the greatest flight range is achieved when the initial speed makes an angle of 45 ° with the horizon (Fig. 106).

At high speeds of movement of bodies, air resistance should be taken into account. Therefore, the flight range of bullets and projectiles in real conditions is not the same as it follows from the formulas that are valid for movement in an airless space. So, for example, with an initial bullet velocity of 870 m/s and an angle of 45°, in the absence of air resistance, the flight range would be approximately 77 km, while in reality it does not exceed 3.5 km.

first cosmic speed

Let us calculate the speed that must be reported to an artificial satellite of the Earth so that it moves in a circular orbit at a height h above the ground.
At high altitudes, the air is very rarefied and offers little resistance to bodies moving in it. Therefore, we can assume that the satellite is affected only by the gravitational force directed to the center of the Earth ( fig.4.4).

According to Newton's second law.
The centripetal acceleration of the satellite is determined by the formula , where h is the height of the satellite above the Earth's surface. The force acting on the satellite, according to the law of universal gravitation, is determined by the formula , where M is the mass of the earth.
Substituting the values F and a into the equation for Newton's second law, we get

From the obtained formula it follows that the speed of the satellite depends on its distance from the Earth's surface: the greater this distance, the lower the speed it will move in a circular orbit. It is noteworthy that this speed does not depend on the mass of the satellite. This means that any body can become a satellite of the Earth if it is given a certain speed. In particular, when h=2000 km=2 10 6 m speed v≈ 6900 m/s.
The minimum speed that must be imparted to a body on the surface of the Earth in order for it to become a satellite of the Earth moving in a circular orbit is called first cosmic speed.
The first cosmic velocity can be found from formula (4.7) if we take h=0:

Substituting into formula (4.8) the value G and values M and R for the Earth, you can calculate the first cosmic velocity for the Earth satellite:

If such a speed is imparted to the body in a horizontal direction near the surface of the Earth, then in the absence of an atmosphere it will become an artificial satellite of the Earth, circling around it in a circular orbit.
Only sufficiently powerful space rockets are able to communicate such a speed to satellites. Currently, thousands of artificial satellites are orbiting the Earth.
Any body can become an artificial satellite of another body (planet) if you tell it the necessary speed.

Movement of artificial satellites

In the works of Newton, one can find a wonderful drawing showing how it is possible to make the transition from a simple fall of a body along a parabola to an orbital motion of a body around the Earth (Fig. 107). “A stone thrown to the ground,” wrote Newton, “will deviate under the action of gravity from a straight path and, having described a curved trajectory, will finally fall to the Earth. If you throw it at a faster speed, it will fall further.” Continuing these considerations, it is easy to come to the conclusion that if a stone is thrown from a high mountain with a sufficiently high speed, then its trajectory could become such that it would never fall to the Earth at all, turning into its artificial satellite.

The minimum speed that must be given to a body near the surface of the Earth in order to turn it into an artificial satellite is called first cosmic speed.
To launch artificial satellites, rockets are used that raise the satellite to a given height and tell it the required speed in the horizontal direction. After that, the satellite is separated from the carrier rocket and continues further movement only under the influence of the Earth's gravitational field. (We neglect the influence of the Moon, the Sun and other planets here.) The acceleration imparted by this field to the satellite is the free fall acceleration g. On the other hand, since the satellite is moving in a circular orbit, this acceleration is centripetal and therefore equal to the ratio of the square of the satellite's speed to the radius of its orbit. Thus,

Where

Substituting expression (43.1) here, we obtain

We got the formula circular speed satellite , i.e., such a speed that the satellite has, moving along a circular orbit with a radius r on high h from the surface of the earth.
To find the first space velocity v1, it should be taken into account that it is defined as the speed of the satellite near the surface of the Earth, i.e. when h< and r≈R3. Taking this into account in formula (45.1), we obtain

Substituting numerical data into this formula leads to the following result:

For the first time, it was possible to tell the body such a tremendous speed only in 1957, when the first in the world was launched in the USSR under the leadership of S.P. Korolev artificial earth satellite(abbreviated AES). The launch of this satellite (Fig. 108) is the result of outstanding achievements in the field of rocket technology, electronics, automatic control, computer technology and celestial mechanics.

In 1958, the first American satellite Explorer-1 was launched into orbit, and a little later, in the 60s, other countries also launched satellites: France, Australia, Japan, China, Great Britain, etc., and many The satellites were launched using American launch vehicles.
At present, the launch of artificial satellites is commonplace, and international cooperation has long been widespread in the practice of space research.
Satellites launched in different countries can be divided according to their purpose into two classes:
1. Research satellites. They are designed to study the Earth as a planet, its upper atmosphere, near-Earth space, the Sun, stars and the interstellar medium.
2. Applied satellites. They serve to satisfy the earthly needs of the national economy. This includes communication satellites, satellites for studying the natural resources of the Earth, meteorological satellites, navigation, military, etc.
AES intended for human flight include manned satellite ships and orbital stations.
In addition to working satellites in near-Earth orbits, the so-called auxiliary objects also circulate around the Earth: the last stages of launch vehicles, head fairings and some other parts that are separated from satellites when they are put into orbit.
Note that due to the enormous air resistance near the Earth's surface, the satellite cannot be launched too low. For example, at an altitude of 160 km, it is able to complete only one revolution, after which it decreases and burns out in the dense layers of the atmosphere. For this reason, the first artificial Earth satellite, launched into orbit at an altitude of 228 km, lasted only three months.
As altitude increases, atmospheric drag decreases and h>300 km becomes negligible.
The question arises: what will happen if a satellite is launched at a speed greater than the first space one? Calculations show that if the excess is insignificant, then the body remains an artificial satellite of the Earth, but it no longer moves in a circle, but along elliptical orbit. With increasing speed, the satellite's orbit becomes more and more elongated, until it finally "breaks", turning into an open (parabolic) trajectory (Fig. 109).

The minimum speed that must be given to a body near the surface of the Earth in order for it to leave it, moving along an open trajectory, is called second cosmic speed.
The second cosmic velocity is √2 times greater than the first cosmic one:

At this speed, the body leaves the area of ​​gravity and becomes a satellite of the Sun.
To overcome the attraction of the Sun and leave the solar system, you need to develop even greater speed - third space. The third escape velocity is 16.7 km/s. Having approximately this speed, the automatic interplanetary station "Pioneer-10" (USA) in 1983 for the first time in the history of mankind went beyond the solar system and is now flying towards Barnard's star.

Examples of problem solving

Task 1. A body is thrown vertically upward at a speed of 25 m/s. Determine the climb height and flight time.

Given: Solution:

; 0=0+25 . t-5 . t2

; 0=25-10 . t 1 ; t 1 \u003d 2.5 s; H=0+25. 2.5-5. 2.5 2 =31.25 (m)

t-? 5t=25; t=5c

H-? Answer: t=5c; H=31.25 (m)

Rice. 1. Choice of reference system

First we must choose a frame of reference. Reference system select the one connected to the ground, the starting point of the movement is indicated by 0. The Oy axis is directed vertically upwards. The velocity is directed upwards and coincides in direction with the Oy axis. Free fall acceleration is directed downward along the same axis.

Let's write down the law of motion of the body. We must not forget that speed and acceleration are vector quantities.

Next step. Note that the final coordinate, at the end, when the body has risen to some height and then fell back to the ground, will be 0. The initial coordinate is also 0: 0=0+25 . t-5 . t2.

If we solve this equation, we get the time: 5t=25; t=5 s.

Let us now determine the maximum lifting height. First, we determine the time of lifting the body to the top point. To do this, we use the velocity equation: .

We have written the equation in general form: 0=25-10 . t1,t 1 \u003d 2.5 s.

When we substitute the values ​​​​known to us, we get that the time of lifting the body, time t 1 is 2.5 s.

Here I would like to note that the entire flight time is 5 s, and the rise time to the maximum point is 2.5 s. This means that the body rises exactly as much time as it will then fall back to the ground. Now let's use the equation we've already used, the law of motion. In this case, we put H instead of the final coordinate, i.e. maximum lifting height: H=0+25. 2.5-5. 2.5 2 =31.25 (m).

After making simple calculations, we get that the maximum height of the body will be 31.25 m. Answer: t=5c; H=31.25 (m).

In this case, we used almost all the equations that we studied in the study of free fall.

Task 2. Determine the height above ground level at which acceleration of gravity is reduced by half.

Given: Solution:

R W \u003d 6400 km; ;

.

H-? Answer: H ≈ 2650 km.

To solve this problem, we need, perhaps, one single data. This is the radius of the earth. It is equal to 6400 km.

Acceleration of gravity is determined on the surface of the Earth by the following expression: . It's on the surface of the earth. But as soon as we move away from the Earth at a great distance, the acceleration will be determined as follows: .

If we now divide these quantities by each other, we get the following: .

Constant values ​​are reduced, i.e. the gravitational constant and the mass of the Earth, but the radius of the Earth and the height remain, and this ratio is 2.

Transforming the equations now obtained, we find the height: .

If we substitute the values ​​in the resulting formula, we get the answer: H ≈ 2650 km.

Task 3.A body moves along an arc with a radius of 20 cm at a speed of 10 m/s. Determine the centripetal acceleration.

Given: SI Solution:

R=20 cm 0.2 m

V=10 m/s

and C - ? Answer: a C = .

Formula to calculate centripetal acceleration known. Substituting the values ​​here, we get: . In this case, the centripetal acceleration is huge, look at its value. Answer: a C =.

"Uniform and uneven movement" - t 2. Uneven movement. Yablonevka. L 1. Uniform and. L2. t 1. L3. Chistoozernoe. t 3. Uniform movement. =.

"Curvilinear motion" - Centripetal acceleration. UNIFORM MOVEMENT OF A BODY IN A CIRCLE Distinguish: - curvilinear movement with a constant modulo speed; - movement with acceleration, tk. speed changes direction. Direction of centripetal acceleration and velocity. The movement of a point in a circle. The movement of a body in a circle with a constant modulo speed.

"Movement of bodies in a plane" - Estimate the obtained values ​​of unknown quantities. Substitute numerical data in a general solution, perform calculations. Make a drawing, depicting interacting bodies on it. Perform an analysis of the interaction of bodies. Ftr. Motion of a body on an inclined plane without friction force. Study of the motion of a body along an inclined plane.

"Support and movement" - An ambulance brought a patient to us. Slender, round-shouldered, strong, strong, fat, clumsy, agile, pale. Game situation “Council of Doctors”. Sleep on a hard bed with a low pillow. Body support and movement. Rules for maintaining correct posture. Correct posture when standing. The bones of children are soft and elastic.

"Space Speed" - V1. THE USSR. So. April 12, 1961 Message to extraterrestrial civilizations. Third cosmic speed. On board Voyager 2 is a disk with scientific information. Calculation of the first cosmic velocity at the Earth's surface. The first manned flight into space. The trajectory of Voyager 1. The trajectory of movement of bodies moving at low speed.

"Body dynamics" - What is the basis of the dynamics? Dynamics is a branch of mechanics that considers the causes of the movement of bodies (material points). Newton's laws are applicable only for inertial frames of reference. Frames of reference in which Newton's first law is satisfied are called inertial. Dynamics. What are the frames of reference for Newton's laws?

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