Who discovered inertia. Who discovered the law of inertia? The fourth law formulated by Newton is the law of universal gravitation

Every body continues to be held in a state of rest, or uniform and rectilinear motion, until and insofar as it is compelled by applied forces to change this state.

The modern wording of the law:

Story

Ancient Greek scientists, judging by the writings that have come down to us, thought about the reasons for the completion and termination of the movement. In "Physics" of Aristotle (4th century BC), the following reasoning is given about motion in emptiness:

However, Aristotle himself believed that emptiness in nature could not exist, and in his other work, Mechanics, it is stated:

Observations really showed that the body stopped when the force pushing it ceased. The natural opposition of external forces (forces of friction, air resistance, etc.) to the movement of the pushed body was not taken into account. Therefore, Aristotle associated the invariance of the speed of movement of any body with the invariance of the force applied to it.

Only two millennia later, Galileo Galilei (1564-1642) was able to correct this mistake of Aristotle. In his Conversations on Two New Sciences, he wrote:

This judgment cannot be derived directly from experiment, since it is impossible to exclude all external influences (friction, etc.). Therefore, here Galileo first applied the method of logical thinking, based on direct observations and similar to the mathematical method of proof "by contradiction". If the inclination of a plane to the horizontal is the cause of the acceleration of a body moving down it, and the deceleration of a body moving up it, then, when moving along a horizontal plane, the body has no reason to accelerate or slow down, and it must be in a state of uniform motion or rest .

Thus, Galileo simply and clearly proved the relationship between force and change in speed (acceleration), and not between force and speed itself, as Aristotle and his followers believed. This discovery of Galileo entered science as Law of inertia. It should be noted that Galileo allowed free movement not only in a straight line, but also in a circle (apparently for astronomical reasons). In its modern form, the law of inertia was formulated by Descartes. Newton incorporated the law of inertia into his system of laws of mechanics as the first law.

Related concepts

inertia- the property of a body to a greater or lesser extent prevent a change in its speed relative to the inertial reference frame when external forces act on it. The measure of inertia in physics is the inertial mass.

see also

Literature

• Leach J.W. Classical mechanics. M.: Foreign. literature, 1961.
• Spassky B.I.. History of physics. M., "Higher School", 1977.
  • Volume 1. Part 1; Part 2
  • Volume 2. Part 1; Part 2
• Kokarev S. S. Three lectures on Newton's laws. Yaroslavl. Sat. Proceedings of the RNEC Logos, vol. 1, 45-72, 2006.

Notes

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Synonyms:

Antonyms:

See what "Inertia" is in other dictionaries:

- (lat. inertia, from iners artless). The general physical property of bodies: the inability to spontaneously change their position both at rest and during movement. Dictionary of foreign words included in the Russian language. Chudinov A.N., 1910. ... ... Dictionary of foreign words of the Russian language

See Mass. Philosophical encyclopedic dictionary. 2010. INERTIA (from Latin inertia - inaction) - in mechanics ... Philosophical Encyclopedia

Inertia- Inertia ♦ Inertie Paradoxical as it sounds, but inertia is primarily a force - the strength of the body to maintain its position in motion or at rest. Indeed, according to the principle of inertia, a material object itself maintains a state of rest or ... Philosophical Dictionary of Sponville

inertia- and, well. inertie lat. inertia. 1. The property of bodies to maintain a state of rest or movement, while some n. force will not bring them out of this state. ALS 1. The horse gave in to the force of inertia, which carried him far beyond the ditch. Tolst. A. Karenina. ... ... Historical Dictionary of Gallicisms of the Russian Language

See laziness... Synonym dictionary

- (from lat. inertia inaction) (inertia), in mechanics, the property of mater. bodies, which is reflected in Newton's 1 m and 2 m laws of mechanics. When ext. effects on the body (forces) are absent or mutually balanced, I. manifests itself in the fact that the body ... ... Physical Encyclopedia

Same as inertia... Big Encyclopedic Dictionary

every body retains a state of rest or uniform rectilinear motion until it is forced to change it under the action of some forces.

IIlaw. This law is rightfully the core of mechanics. It relates the change in body momentum (momentum) with the force acting on it, i.e. the change in the momentum of the body per unit time is equal to the force acting on it and occurs in the direction of its action. Since in Newtonian mechanics mass does not depend on velocity (in modern physics, as we will see later, this is not the case), then

, where a is the acceleration of the reaction are equal in magnitude and opposite in direction. The mass in this expression appears as measure of inertia . It is easy to see that with a constant impact force, the acceleration that can be given to a body is the smaller, the greater its mass.

Law III reflects the fact that the action of bodies is always in the nature of interaction, and that the forces of action and reaction are equal in magnitude and opposite in direction.

The fourth law formulated by Newton is the law of universal gravitation.

The logical chain of this discovery can be built as follows. Reflecting on the motion of the Moon, Newton concluded that it is kept in orbit by the same force under which the stone falls to the ground, i.e. gravitational force: "The moon gravitates towards the Earth and by the gravitational force constantly deviates from rectilinear motion and is kept in its orbit." Using the formula of his contemporary Huygens for centripetal acceleration and astronomical data, he found that the centripetal acceleration of the Moon is 3600 times less than the acceleration of a stone falling to the Earth. Since the distance from the center of the Earth to the center of the Moon is 60 times the radius of the Earth, we can assume that The force of gravity decreases with the square of the distance. Then, on the basis of Kepler's laws describing the motion of the planets, Newton extends this conclusion to all planets. ( “The forces by which the principal planets deviate from rectilinear motion and are kept in their orbits are directed towards the Sun and are inversely proportional to the squares of the distances to its center»).

Finally, having stated the position about the universal nature of the forces of gravity and their identical nature on all planets, showing that “the weight of a body on any planet is proportional to the mass of this planet”, establishing experimentally the proportionality of the mass of a body and its weight (gravity), Newton concludes that the force of gravity between bodies is proportional to the mass of these bodies. So the famous law of universal gravitation was established, which is written as:

Where g is the gravitational constant, first experimentally determined in 1798 by G. Cavendish. According to modern data g\u003d 6.67 * 10 -11 N × m 2 / kg 2.

It is important to note that in the law of universal gravitation, mass acts asgravity measures , i.e. determines the force of gravity between material bodies.

The importance of the law of universal gravitation lies in the fact that Newton thusdynamically substantiated the Copernican system and Kepler's laws.

Note.The fact that the force of gravity is inversely proportional to the square of the distance, some scientists guessed even before Newton. But only Newton was able to logically substantiate and convincingly prove this law with the help of the laws of dynamics and experiment.

Attention should be paid to an important fact testifying to Newton's deep intuition. In fact, Newton established a proportionality between weight Andweighing , which meant thatmass is not only a measure of inertia, but a measure of gravity . Newton was well aware of the importance of this fact. In his experiments, he established that the inertial mass and the gravitational mass coincide with an accuracy of 10 -3 . Subsequently, A. Einstein, considering the equality of inertial and gravitational massesfundamental law of nature , put it at the basis of the general theory of relativity, or GR. (Interestingly, during the creation of general relativity, this equality was proved with an accuracy of 5 × 10 -9 , and it has now been proven to within 10 -12‑ .)

In the third part of the book, Newton outlined the General System of the World and celestial mechanics, in particular, the theory of compression of the Earth at the poles, the theory of ebbs and flows, the motion of comets, perturbations in the motion of planets, etc. based on the law of gravity.

Newton's statement that the Earth is compressed at the poles was experimentally proven in 1735-1744. as a result of measuring the Earth's meridian arc in the equatorial zone (Peru) and in the north (Lapland) by two expeditions of the Paris Academy of Sciences.

The next great success of the law of universal gravitation was the prediction by the scientist Clairaut of the time of the return of Halley's comet. In 1682, Halley discovered a new comet and predicted its return to the sphere of terrestrial observation after 76 years. However, in 1758 the comet did not appear, and Clairaut made a new calculation of the time of its appearance on the basis of the law of universal gravitation, taking into account the influence of Jupiter and Saturn. Calling the time of her appearance - April 4, 1759, Clairaut was mistaken by only 19 days.

(Successes in the theory of gravitation in solving the problems of celestial mechanics continued into the 19th century. So in 1846, the French astronomer Le Verrier wrote to his German colleague Halle: “Point your telescope at the point of the ecliptic in the constellation of Aquarius at longitude 326 degrees, and you will find within one degree of this place a new planet with a noticeable disk, having the appearance of a star of approximately the ninth magnitude.” This point was calculated by Le Verrier and independently of him by Adams (England) on the basis of the law of universal gravitation in the analysis of the observed "irregularities" in the motion of Uranus and the assumption that they are caused by the influence of an unknown planet. Indeed, on September 23, 1846, Galle discovered a new planet at the specified point in the sky. This is how the words "The planet Neptune is discovered at the tip of a pen" were born.)

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Law of inertia

A.I. Somsikov

The erroneous understanding of the 1st law of physics, also called Newton's first law or Galileo's law of inertia, is revealed.

Galileo's law of inertia, also called Newton's first law, in the applicable formulation means something like this: "In the absence of force, the motion of a body is uniform, rectilinear, not limited in time and space."

Since both of these unboundednesses are practically unverifiable, Galileo's proof of this is purely logical.

This experiment is an observation of the movement of a body along an inclined plane with positive and negative angles of inclination, corresponding to the body rolling down or rolling up.

Observation reveals in this case the presence of accelerations of opposite signs.

It follows from here that the zero angle of inclination should correspond to zero acceleration, i.e. uniform motion, not limited in time and space, in other words - eternal and infinite.

This logical conclusion looks flawless even with the fact that real movements are limited.

They are simply assigned a slight negative acceleration caused by the postulated frictional resistance of the body with the reference plane due to their contact.

Since scientific research is akin to a criminal investigation, in the language of detectives, this is called a false trail, designed to divert attention. An absolutely secondary observation, only imitating its utmost thoroughness, diverting the observer's attention from a really major logical error. And what is truly amazing is the ease with which this bait is swallowed, along which everyone rushes in unison.

Indeed, this assumes that in the absence of contact between the bodies, which creates this friction, the acceleration would be really zero.

But is such a conclusion possible?

First of all, the experiment did not fulfill the initial requirement - the absence of force.

It has this force, although it is compensated by the counteracting force from the flat surface. But this, after all, means that the elimination of the touch of the bodies also eliminates the reaction force as a required condition for compensating the force. And this means the required condition for the supposed zero acceleration.

But even in the ideal case - while maintaining the touch of the bodies (necessary to create a counterbalancing force) and the complete absence of friction resistance (i.e. under the conditions of a mental experiment), is this logical conclusion true - zero acceleration?

The movement under consideration is directed perpendicular to the acting forces.

The opposing force of a flat surface is always perpendicular to it and to the movement, but what about the compensated initial force?

Provided that movement is not limited in time and space?

It's about the force of gravity.

It is also centered in the direction of the current acceleration, i.e. to the origin of the inertial frame of reference ISO, aligned with the center of mass, in this case, with the center of the Earth.

It is required to have the acceleration caused by attraction perpendicular to the reference plane.

In the initial position, this condition is satisfied.

With unlimited spatial displacement, the acceleration acquires an angular turn towards the reference point of the ISO, as a result of which its projection on the direction of movement in the general case has a non-zero value.

This projection has a braking effect on the movement, and already without any friction.

This violates the requirement of the absence of force in the direction of motion or its perpendicularity to this direction.

Consequently, the supposed unlimitedness in time and space of uniform rectilinear motion turns out to be impossible.

Galileo's experiment is performed only on a limited scale, and its postulated unlimitedness is an absolutely unacceptable extrapolation.

It also follows from this that the condition for the uniformity of motion is the continuous preservation of its direction perpendicular to the acceleration.

Such preservation is possible in one single case of body movement along a circle with a radius of curvature that maintains a constant value relative to the origin of the reference frame.

Therefore, the true logical conclusion, which follows directly from Galileo's experiment, is: "in the presence of a centered force compensated by an oppositely directed force, the movement of the body is a uniform rotation about the starting point of the ISO, not limited in time and space."

When touching the surface is removed, replaced by centrifugal force, this is actually observed in countless examples of such rotations from the Moon and other objects of a cosmic scale to the microcosm represented by the scale of an atom.

But what about the real, true lack of power?

Let's modernize Galileo's experiment, even if just mentally.

To do this, it is necessary that the movement perpendicular to the force of attraction be at such a distance from the reference point of the ISO, at which the value of this force could simply be neglected.

This can always be achieved by an appropriate choice of a sufficiently large scale.

Such movement can indeed remain uniform and rectilinear on an unlimited scale of space and time, in the considered IFR.

Well, is this ISO itself spatially immobile?

No, it also moves, and at an accelerated rate, but only in a different IFR, formed, for example, by the solar system.

Consequently, the movement under consideration, which is uniform in the initial IFR, turns out to be accelerated in another IFR.

It is possible to continue the mental experiment by removing this movement even further, at such a distance from the solar system, at which its movement in this IFR will be already uniform. But, firstly, this will not happen in the original "Galilean" (terrestrial) IFR, where it will still remain accelerated.

And secondly, the solar system itself, in turn, is moving rapidly relative to the center of our Galaxy, which forms the third IFR.

It is possible to continue increasing the cosmic scale of the Galilean uniform and rectilinear motion, taking it out of the Galaxy.

But even this does not mean at all that, firstly, the movement will remain uniform in the previously abandoned terrestrial and solar IFRs.

And secondly, the Galaxy itself, in turn, can move rapidly in the system of other galaxies relative to another center formed by their nearest or remote environment.

Thus, it turns out that Galileo's law of inertia or the first law of Newton's mechanics (and the first law of physics in general) is not satisfied not only on a limited scale, but also on an unlimited one, but simply speaking, nowhere and never, due to the centering of gravity forces, so that his rationale is wholly flawed.

It is strange that this error has so far gone unnoticed.

In general, this is a feature of the old sciences: arguments that would be immediately refuted if they were presented now, quietly exist, being not noticed after a certain time, when researchers do not even think of subjecting them to a second logical examination.

Perhaps a special independence of thought is needed to embark on a path that is considered long gone, without any thoughts about its guaranteed "results", out of sheer love for scientific truth.

Meanwhile, for the first time, after all, they began to reason independently, moreover, of course, by no means immediately immaculately and not even too confidently quite recently - some three hundred years ago!

So the very possibility of inaccuracies and even simple errors for those who have experience in independent reasoning seems very likely and even almost inevitable.

It would be incredible not to find them at all, of course, with some careful analysis.

In the meantime, they are looking (in vain) at Einstein, while it would be worth starting with Newton or Copernicus.

Einstein is, of course, a crisis, but a very late one, laid down much earlier by his predecessors, the pioneers.

Bibliography

For the preparation of this work, materials from the site http://www.sciteclibrary.ru were used.

Newton's 1st law or law of inertia was established by Galileo Galilei in 1632, but only rigorously formulated by Isaac Newton in 1686. It is the first of the 3 laws of traditional mechanics and in its modern formulation it sounds like this:

There are such systems of reference, in relation to which the body (real point), in the absence of external influences on it (or with their mutual compensation), retains a state of rest or uniform rectilinear motion. (Source)

To this formulation is usually added: such frames of reference are called inertial. Therefore, Newton's 1st law is a definition and statement about the existence of inertial frames of reference. But this meaning is often missed in simple textbooks of physics, where it is often possible to meet such formulations:

Any body, free from the influence of other bodies, keeps its speed constant.(Source)

Such formulations give rise to an erroneous memory, as if Newton's first law is only a personal case of the second, which states that the acceleration of a body is proportional to the force acting on it. It should, however, be noted that such formulations formally follow Newton, who does not have an obviously formulated concept of a frame of reference and an idea of ​​the existence of various types of frames of reference. Here is Newton's first law:

Any body continues to be held in its own state of rest or uniform rectilinear motion, until and since it is forced by applied forces to change this state. (Isaac Newton, Mathematical Principles of Natural Philosophy, M., Nauka, 1989, translated from Latin by Academician A.N. Krylov)

Unique (Latin) formulation of the first law:

Corpus omne preseverare in statu suo quiescendi vel movendi uniformiter in directum, nisi quatenus illud a viribus impressis cogitur statum suum mutare.(Ibid.)

Sources:

Who discovered the law of inertia?

Newton's 1st law or the law of inertia was established by Galileo Galilei in 1632, but was strictly formulated only by Isaac Newton in 1686. It is the first of the 3 laws of traditional mechanics and in the modern formulation it sounds like this: There are such frames of reference, relative to which the body (real point) in the absence of external influences on it (or with them ...

What does the first rule of mechanics sound like, and who discovered the law of inertia? Is it true that more than one scientist dealt with this issue?

When and by whom was the law of inertia discovered?

In 1632, Galileo Galilei discovered one of the three laws of classical mechanics. It was completed by Isaac Newton in 1686. The wording of the rule is:

Thus, the concept of a frame of reference in physics is given. The pattern was established as a result of practical observations and the identification of patterns in the physical properties of objects. The conclusions drawn are applicable only to objects moving at low speed. These are not applicable to phenomena that occur with indicators of the movement of light.

Dynamics is a branch of mechanics about the interaction of bodies. In addition to the first law, finalized by Newton, the second law is also distinguished - described by Descartes in his work "Beginnings" in 1644. The laws of the third were established by Christian Huygens in 1669.

The essence of the law is as follows: an isolated body is considered, having isolation from other objects of the external world and their influence. Rest has a relative value, since the oscillation of an object in different reference systems reaches different values. In one, rest or movement with a constant indicator is noted, in the other - with acceleration according to the established module in a given direction.

In the first law of dynamics, a class is singled out - inertial systems. Since movement occurs when other objects act on the object, then during its subsequent isolation, the body retains the module and direction of movement - and this phenomenon is called inertia. Its manifestations are called "Newton's First Law".

When is the law broken?

The specified mechanism of action applies to all objects located on the surface or. With deviations, a violation of Newton's law is noted, which is due to the rotation of the planet around its axis. As an example of the manifestation of the properties of a non-inertial system is the manifestation of mechanical laws in the behavior of Foucault's invention. The object is a ball-pendulum, fixed on a thin thread and swung to fluctuations of small amplitude. If the object were in an inertial system, then the swing plane would be stable. However, due to movement around the property, the axis of the Earth is shifting.

Thus, it is known who discovered the law of inertia of the first order. It was he who became the basis for the creation of the basic rules of mechanics and the establishment of new laws in physics.