On the facade of the Ministry of Justice in Paris under one of the windows in marble, the horizontal line and the inscription "Meter" carved. Such a miniature detail is barely noticeable against the background of the magnificent building of the Ministry and the Vandom Square, but this line is the only one from the remaining "standard standards", which were located throughout the city over 200 years ago in an attempt to submit a new universal system of measures - metric.

We often accept a system of measures as proper and not even think about what story is under its creation. The metric system that was invented in France is official worldwide, with the exception of the three states: the United States, Liberia and Myanmar, although in these countries it is used in some areas like international trade.

Can you imagine what our world would be if the system of measures was everywhere, like the usual situation with the currencies? But everything was so before the French revolution, which broke out at the end of the 18th century: Then the units of measures and scales were different not only between individual states, but even within the same country. Almost every French province existed their units of measures and weights that are unsupported with units used by their neighbors.

The revolution brought the wind of change and in this sphere: in the period from 1789 to 1799, activists sought to transfer not only government regime, but also thoroughly change the society by changing the traditional foundations and habits. For example, in order to limit the influence of the Church to social life, the revolutionaries presented a new republican calendar in 1793: he consisted of decadatholic days, one hour was 100 minutes, one minute - 100 seconds. This calendar fully corresponded to the desire of the new government to introduce a decimal system in France. This approach to the calculus of time did not take place, but the decimal measures have come to taste to taste, which was based on meters and kilograms.

The first scientific minds of the republic worked on the development of a new system of measures. Scientists intended to invent the system that would submit logic, not local traditions or wishes of the authorities. Then they decided to build on the fact that they gave us nature - the reference meter was to be equal to one decade-million distance from the North Pole to the Equator. This distance was measured at the Paris Meridian, which was held through the building of the Paris Observatory and shared it into two equal parts.

In 1792, the scientists Jean-Batist Joseph Dobrbre and Pierre Meson went along Meridian: the goal of the first was the city of Dunkirk in the north of France, the second followed south to Barcelona. Using the latest equipment and mathematical process of triangulation (the method of constructing a geodesic network in the form of triangles, in which their corners and some of the parties are measured) they calculated to measure the meridian arc between the two cities that were at sea level. Then with the help of the extrapolation method (the method of scientific research, consisting in the spread of the conclusions derived from observation over one part of the phenomenon, to another part of it) they were going to calculate the distance between the Pole and the Equator. According to the primary idea for all measurements and the creation of a new universal system of measures, scientists planned to spend a year, but as a result, the process stretched for whole seven years.

Astronomers faced the fact that in those hectic times people often perceived them with great caution and even hostile. In addition, without the support of the local population, scientists were often not allowed to work; There have been cases when they received injuries, climbing the highest dots in the district like the domes of churches.

From the top of the dome of Pantheon, the Dake made measurements in Paris. Initially, the King of Louis XV erected the Pantheon building for the church, but the Republicans equipped it under the central geodetic station of the city. Today, Pantheon serves as a mausoleum for the heroes of the revolution: Voltaire, Rene of Descartes, Viktor Hugo, and others. In those days, the building also performed the functions of the museum - all the old standards of measures and the scales were kept there, which sent residents of all France in anticipation of a new perfect system.

Unfortunately, despite all the efforts of scientists spent on the development of a decent replacement for old units of measurement, no one wanted to use new system. People refused to forget the usual methods of measurement, which were often closely related to local traditions, rituals and life. For example, El is a unit of measurement of tissue - as a rule, it was equal to the size of weaving machines, and the size of arable land was calculated exclusively in the days, which it was necessary to spend on its processing.

Paris authorities were so outraged by the refusal of the residents to use a new system of measures, which often sent the police to local markets so that they were injected into circulation. As a result, in 1812, Napoleon threw the policy of introducing a metric system - it was still taught in schools, but people allowed to use the usual units of measures to 1840, when the policy was resumed.

France took almost a hundred years to fully switch to the metric system. It was finally possible, but not due to the perseverance of the government: France quickly moved towards the industrial revolution. In addition, it was necessary to improve the Maps for military purposes - this process required accuracy that it was not possible without a universal system of measures. France confidently went to the international market: In 1851, the first international fair took place in Paris, on which the participants of the event were shared by their achievements in the field of science and industry. The metric system was simply necessary to avoid confusion. The construction of the Eiffel Tower with a height of 324 meters was timed to the International Fair in Paris in 1889 - then it became the highest manual structure in the world.

In 1875, an international bureau of measures and scales was established, whose headquarters is located in a quiet suburb of Paris - in the city of Sevr. The Bureau supports international standards and unity of seven measures: meter, kilogram, second, ampere, Kelvin, Mol and Candela. There is a standard of a meter from platinum, from which previously made copies of the standards earlier and sent to other countries as a sample. In 1960, the General Conference of Mens and Scales adopted a meter based on the length of the light wave - thus making the standard even closer to nature.

At the headquarters of the Bureau also contains a reference kilogram: it is placed in the underground storage versus three glass caps. The standard is made in the form of a platinum and iridium alloy cylinder, in November 2018 the standard will be revised and overridden using a quantum constant plank. The resolution on the revision of the international system of units was adopted back in 2011, but due to some technical characteristics of the procedure, it was not possible until recently.

Definition of units of measures and weights is a very labor-intensive process, which is accompanied by various difficulties: from the nuances of experiments to financing. The metric system underlies progress in many areas: in science, economics, medicine, etc., it is vital for further research, globalization and improving our understanding of the universe.

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International unit

Creation and development of a metric system

The metric measures was created at the end of the XVIII century. In France, when the development of industry trade ultimately urged the replacement of many lengths of length and mass selected arbitrarily, uniform unified units, which meter and kilogram.

Initially, the meter was defined as 1/40,000,000 part of the Paris Meridian, and kilogram - as a mass of 1 cubic water decimeter at a temperature of 4 s, i.e. Units were based on natural references. This consisted of one of the most important features of metric systems, which determined its progressive value. The second important advantage was the decimal unit of units, which corresponds to the calculus adopted system, and a single way to form their names (including the corresponding prefix in the name: Kila, Hekto, Deca, Santi and Milli), which went rid of complex transformations of some units to others and eliminated confusion in names.

The metric system of measures has become the basis for unifying units worldwide.

However, in subsequent years, the metric system of measures in the original form (m, kg, m, m. AR and six decimal consoles) could not satisfy the demands of the developing science and technology. Therefore, each knowledge branch chose comfortable units and units. Thus, the system of centimeter - gram - second (SGS) adhered to physics; The technique found a wide distribution system with basic units: meter - kilogram-power - second (ICGSS); in theoretical Electrical Engineering there were one of the other systems of units derived from the SGS system; In the heat engineering, systems based on, on the one hand, on a centimeter, gram and second, on the other hand, - on a meter, kilogram and seconds, with the addition of a temperature unit - degrees Celsius and generated units of the amount of heat - calories, cyocaloria, etc. . In addition, there were use of many other non-system units: for example, units of work and energy - kilowatt-hour and liter-atmosphere, pressure units - millimeter of mercury pillar, a millimeter of a water column, bar, etc. As a result, a significant number of metric systems of units was formed, some of them covered certain comparatively narrow industries, and many non-system units, the basis of whose definitions metric units were laid.

Simultaneous use in certain areas led to clogging of many calculated formulas with numerical coefficients, not equal unitsthat greatly complicated calculations. For example, the technique has become normal application To measure the mass of the unit of the ISS system - kilogram, and to measure the force of the unit of the MKGSS - kilogram system. This seemed comfortable from the point of view that the numerical values \u200b\u200bof the mass (in kilograms) and its weight, i.e. The forces of attraction to the ground (in kilogram-forces) were equal (with accuracy sufficient for most practical cases). However, the consequence of equating the values \u200b\u200bof heterogeneous substantially values \u200b\u200bwas the appearance of 9.806 65 numerical formulas (rounded 9.81) and to mix the concepts of mass and weight, which gave rise to many misunderstandings and errors.

Such a variety of units and associated inconvenience spawned the idea of \u200b\u200bcreating a universal system of units of physical quantities for all branches of science and technology that could replace everything existing systems and individual generating units. As a result of the work of international metrological organizations, such a system was developed and obtained the name of the international system of units with a reduced designation SI (system international). Xi was adopted by the one-General Conference on measures and weights (GKMV) in 1960 as modern form metric system.

Characteristics of the International Unit System

The versatility C is ensured by the fact that the seven major units laid on its basis are units of physical quantities reflecting the basic properties of the material world and make it possible to form derivative units for any physical quantities in all sectors of science and technology. The same goals are also the additional units necessary for the formation of derivative units dependent on flat and corngle. The advantage of C in front of other units systems is the principle of constructing the system itself: C was constructed for some system of physical quantities, which make it possible to present physical phenomena in the form of mathematical equations; Some of the physical quantities are accepted by the basic and all other are expressed through them - derivatives of physical quantities. For the basic values \u200b\u200bof units, the size of which is agreed at the international level, and for the remaining values \u200b\u200bderived units are formed. Thus, the units constructed and the units included in it are called coherent, since the condition is constructed that the relationship between numerical values \u200b\u200bof values \u200b\u200bexpressed in SI units does not contain coefficients other than those included in the originally selected equations that bind values. The coherence of UN units when applied allows to a minimum to simplify the calculated formulas due to the release of them from the transfer coefficients.

Si eliminated multiplicity of units to express the values \u200b\u200bof the same kind. For example, instead of a large number of pressure units used in practice, only one unit is Pascal.

The establishment for each physical value of its unit made it possible to distinguish between the concept of mass (a unit of C kilograms) and forces (CO - Newton Unit). The concept of mass should be used in all cases when the body or substance property is referred to, characterizing their inertia and the ability to create a gravitational field, the concept of weight - in cases where the force resulting from the interaction with the gravitational field.

Determination of the main units. And it is possible with a high degree of accuracy, which ultimately not only allows you to increase the accuracy of measurements, but also to ensure their unity. This is achieved by the "materialization" of units in the form of standards and transmission from the size of the dimensions of the measurement tools using a set of sample measurement tools.

The international system of units thanks to its advantages has been widespread in the world. Currently, it is difficult to call a country that would not have implemented SI, would be at the implementation stage or did not make decisions on the implementation of SI. So, countries that previously used the English system of measures (England, Australia, Canada, the USA, etc.) also accepted C.

Consider the structure of building an international system of units. Table 1.1 shows the main and additional units of C.

Derivatives of SI units are formed from the main and additional units. Derivatives of SI units with special names (Table 1.2) can also be used to form other derivatives of SI units.

Due to the fact that the range of values \u200b\u200bof most measured physical quantities currently can be very significant and only units are uncomfortable, since, as a result of the measurement, too large or small numeric values \u200b\u200bare obtained, the use of decimal multiple and dollane from units which are formed using multipliers and consoles shown in Table 1.3.

International unit

On October 6, 1956, the International Committee of Measures and Scales considered the recommendation of the Commission on Units and adopted the following important decision on the establishment of an international system of measurement units:

"International Committee of Measures and Scales, taking into account the task received from the Ninth General Conference on Measures and Sighs in its Resolution 6, regarding the establishment of a practical system of units of measure, which could be adopted by all countries that signed the Metric Convention; Taking into account all documents Received from 21 countries that answered the survey proposed by the Ninth General Conference on Measures and Sighs; Taking into account the resolution 6 of the Ninth General Conference on Measures and Weighs, which establishes the choice of the main units of the future system, recommends:

1) To be called the "international system of units", a system based on the main units adopted by the Tenth General Conference and are as follows;

2) To apply the units of this system listed in the following table, not predestine other units that can be added subsequently. "

At the session in 1958, the International Committee of Measures and Scales discussed and decided on a symbol for an abbreviated name "International Unit System" name. A symbol consisting of two letters Si (initial letters of words System International - international System).

In October 1958, the International Committee of Legislative Metrology adopted the following resolution on the issue of the international system of units:

metric measure system weight

"The International Committee of Legislative Metrology, having gathered at the plenary meeting on October 7, 1958 in Paris, announces accession to the resolution of the International Committee of Measures and Weighs on the establishment of the International Measurement Units (SI).

The main units of this system are:

meter - kilogram-second-ampere-degree Kelvin-Candle.

In October 1960, the issue of the international system of units was considered at the eleventh General Conference on Measures and Sighs.

On this issue, the conference adopted the following resolution:

"The Eleventh General Conference on Measures and Sighs, taking into account the resolution 6 of the Tenth General Conference on Measures and Sighs, in which it adopted six units as a base for establishing a practical measurement system for international relations, taking into account resolution 3 adopted by the International Committee of Measures and Weighs in 1956, and taking into account the recommendations adopted by the International Committee of Measures and Scales in 1958, related to the abbreviated name of the system and to the filing for the formation of multiple and dolly units, decides:

1. Assign a system based on six major units, the name "International Unit System";

2. To establish an international abbreviation name of this system "Si";

3. Form the names of multiples and dolle units by following the following consoles:

4. Apply in this system the following units, not predetermined which other units can be added in the future:

The adoption of the international system of units was an important progressive act, summarizing a large long-term preparatory work in this direction and summarized the experience of scientific and technical circles. different countries and international organizations on metrology, standardization, physics and electrical engineering.

The decisions of the General Conference and the International Committee of Measures and Lights on the International System of Units are taken into account in the recommendations of the International Organization for Standardization (ISO) on units of measurements and have already been reflected in the legislative provisions on units and in standards per units of some countries.

In 1958, the GDR approved a new provision on units of measurements, built on the basis of the international system of units.

In 1960, the International Unit System was adopted in the Governmental Law on Units of Measuring the Hungarian People's Republic.

State Standards of the USSR per units 1955-1958. Based on the system of units adopted by the International Committee of Measures and Libra as an international unit of units.

In 1961, the Committee of Standards, measures and measuring instruments at the Council of Ministers of the USSR approved GOST 9867 - 61 "International Units", which establishes the preferred use of this system in all areas of science and technology and in teaching.

In 1961, the international system of units in France and in 1962 in Czechoslovakia are legalized by the government decree.

The international system of units was reflected in the recommendations of the International Union of Clean and Applied Physics, adopted by the International Electrotechnical Commission and a number of other international organizations.

In 1964, the international system of units was based on the "Table of Units of Legal Measurement" of the Democratic Republic of Vietnam.

In the period 1962 to 1965 In a number of countries, laws on the adoption of an international system of units were issued as mandatory or preferred and standards per units.

In 1965, in accordance with the instructions of the XII General Conference on measures and weights, the International Bureau of Measures and Libra conducted a survey regarding the provision with the adoption of SI in countries who joined the Metric Convention.

13 countries have accepted C as a mandatory or preferred.

In 10 countries, the application of the international system of units is allowed and prepared for the revision of laws in order to impart a legal, mandatory nature of this system in a given country.

In 7 countries C are allowed as optional.

At the end of 1962, a new recommendation was published by the International Commission on Radiological Units and Measurements (Spring), dedicated to the values \u200b\u200band units in the field of ionizing radiation. In contrast to the previous recommendations of this commission, which were mainly devoted to special (non-system) units for measuring ionizing radiation, the new recommendation includes a table in which the units of the international system are in the first place for all values.

On October 14-16, 1964, the seventh session of the International Committee of Legislative Metrology, which included representatives of 34 countries that signed the Intergovernmental Convention, the establishment of an international organization of legislative metrology, was adopted on the implementation of the following resolution:

"The International Committee of Legislative Metrology, taking into account the need to quickly spread the international system of SI units, recommends the preferred use of these SI units with all measurements and in all measuring laboratories.

In particular, in temporary international recommendations. Received and common International Conference Legislative Metrology, these units should be used preferably to graduate measuring devices and devices to which these recommendations are applied.

Other units whose application is allowed by these recommendations is allowed only temporarily, and they should be avoided as soon as possible. "

The International Committee of Legislative Metrology created the Secretariat-Rapporteur on the topic "Units of Measurements", whose task is to develop a model draft legislation on units of measurements based on the international system of units. The conduct of the Rapporteur Secretariat on this topic took on Austria.

Advantages of the international system

International system universal. It covers all areas physical phenomena, all industries and national economy. The international system of units organically includes such long-widespread and deeply rooted private systems in the art, as a metric system of measures and a system of practical electrical and magnetic units (amp, volts, Weber, etc.). Only the system in which these units entered could claim recognition as universal and international.

The units of the international system are most sufficiently convenient in their size, and the most important of them have convenient in practice their own names.

Building an international system meets the modern level of metrology. This includes the optimal selection of major units, and in particular their numbers and sizes; coherence (coherence) of derivatives of units; rationalized form of electromagnetism equations; The formation of multiple and dolle units through decimal consoles.

As a result, various physical quantities have in the international system, as a rule, and different dimensions. This makes it possible a full-fledged dimensional analysis, preventing misunderstanding, for example, when controlling the calculation. Indicators of dimension in C are integer, and not fragile, which simplifies the expression of derivatives through the main and generally operating with dimension. 4P and 2P coefficients are present in those and only those equations of electromagnetism, which relate to fields with spherical or cylindrical symmetry. The method of decimal consoles inherited from the metric system allows you to cover the huge ranges of changes in physical quantities and ensures the correspondence of the X decimal system.

The international system is inherent sufficient flexibility. It allows for a certain number of non-system units.

C - live and developing system. The number of major units can be even increased if it is necessary to cover any additional field of phenomena. In the future, the mitigation of some of the regulatory rules in force also is not excluded.

The international system, as its name itself, is also intended to become the universally used unique system of physical quantities. Unification of units represents a long overwhelming need. Already, Si made unnecessary numerous units.

The international system of units is adopted in more than 130 countries of the world.

The international system of units is recognized by many influential international organizations, including the United Nations Organization on Education, Science and Culture (UNESCO). Among those recognized by the International Organization for Standardization (ISO), the International Organization of Legislative Metrology (Moldova), International Electrotechnical Commission (IEC), International Union of Clean and Applied Physics, etc.

Bibliography

1. Burdun, Vlasov A.D., Murin B.P. Units of physical quantities in science and technology, 1990

2. Ershov V.S. The introduction of the international system of units, 1986.

3. Kama D, Kremer K. Physical bases Units of measurement, 1980.

4. Novosillese. The history of the main units C, 1975.

5. Damn A.G. Physical quantities (terminology, definitions, designations, dimension), 1990.

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Blaze Pascal, the concept of atmospheric pressure

(19. VI.1623 - 19. VIII.1662) - French mathematician, physicist and philosopher. R. in Clermont Ferran. Received home education. In 1631, together with the family moves to Paris. E. Pascal and some of his buddies - M. Mersenna, J. Roberval and others - Mathematics and physics were collected every week. These meetings over time turned into scientific. Meetings. On the basis of this mug was created Paris. An (1666). From 16 years P. participated in the work of the circle. At this time, he wrote his first job about the conical sections, in Ki-Roy expressed one of the important theorems of projective geometry: the intersection points of the opposite sides of the hexagon, inscribed in the conical section, lie on one straight line (Pascal theorem).

Physical studies are mainly in the hydrostatics, where the main law formulated in 1653, according to which the pressure on the liquid is transmitted to it evenly unchanged in all parties - the law of Pascal (this property of fluid was also known to its predecessors), established the principle of operation hydraulic press. He moved a hydrostatic paradox, which thanks to him became widely known. Confirmed existence atmospheric pressure, repeating in 1646 the experience of torrchelli with water and wine. Expressed the idea that atmosphere pressure decreases with a height (according to its idea in 1647 an experiment was carried out, which testified that at the top of the mountain, the level of mercury in the tube is lower than at the base), demonstrated the elasticity of the air, proved that the air has a weight, discovered that the barometer indications depend on humidity and air temperature, and therefore it can be used to predict the weather.

In mathematics devoted a number of works by arithmetic rows and binomial coefficients. In the "Treatise on an arithmetic triangle" gave mev. Pascal's triangle - a table, in K-Roy Coiff. The decomposition (a + b) of the n must of different n are in the form of a triangle. Binomial Coeff. Formed a complete Mat for the method developed by him. Induction - this was one of the most important discoveries. The new thing was that binomial coefficients. They performed here as numbers of combinations from p elements on M and then used in the tasks of probability theory. Until that time, none of the mathematicians did not calculate the events. Pascal and P. Fermanshley Key to solve such tasks. In their correspondence, probability theory and combinatorics are substantiated scientifically, and therefore Pascal and the farm are considered the founders of the new region of mathematics - probability theory. A great contribution introduced in the development of calculus infinitely small. Studying cycloid offered general methods Definitions of quadratuts and centers of gravity Split. Curves, opened and applied such methods, to-rye give reason to consider it one of the creators of the calculus of infinitely small. In "Treatise about the sines of a quarter of a circle", calculating the integrals trigonometric functionsIn particular, Tangent, introduced elliptical integrals, which later played an important role in the analysis and its applications. In addition, proved a number of theorems relating to the replacement of variables and integration in parts. Pascal has, although in undeveloped form, ideas about the equality of the differential as the main linear part of the increment to the most increment and the properties of equivalent infinitely small values.

Back in 1642, the counting machine for two arithmetic action was constructed. The principles based on this machine have become late in the design of counting machines.

Its name called a pressure unit - Pascal.

Alessandro Volt, Wilt Wolt, Electrical, Electrometer

Alessandro Volta was born on February 18, 1745 in the small Italian city of Como, located near Lake Como, close to Milan. In it soon woke up for learning electrical phenomena. In 1769, he publishes work on the Leiden Bank, in two years - about the electric car. In 1774, Volta becomes a teacher of physics at school in Como, invents the electronics, then the eudiometer and other devices. In 1777, he becomes a professor of physics in Pavia. In 1783, there is an electroscope with a capacitor, and from 1792. It has been engaged in "animal electricity". These classes led it to the invention of the first galvanic element.

In 1800, he built the first electric current generator - volts pillar. This invention delivered him worldwide glory. He was elected a member of the Parisian and other academies, Napoleon made him a graph and senator of the Italian kingdom. But in Science Volta after his great opening no longer done anything significant. In 1819, he left the professors and lived in his hometown of Como, where he died on March 5, 1827 (one day with Laplas and one year old with Frenelhem).

Volts pillar

Starting in 1792, work on the "animal electricity", Volta repeated and developed the experiments of Galvani, fully accepting his point of view. But in one of the first letters sent from Milan on April 3, 1792, he indicates that the muscles of the frog are very sensitive to electricity, they "amazingly react to electricity", completely elusive even for the Bennet's electroscope, the most sensitive of all (made of two strips of the finest gold or silver). Here, the beginning of the subsequent allegation of the Volta is that "the prepared frog represents, if you can express it, an animal electronometer is incomparably more sensitive than any other the most sensitive electron."

Volta as a result of a long series of experiments came to the conclusion that the cause of muscle contraction is not the "animal electricity", but contact of heterogeneous metals. "The initial reason for this electric current - writes Volta," Whatever it is, the metals themselves are due to the fact that they are different. It is they who in their own ways are pathogens and engines, while the animal organ, the nerves themselves are only passive. " The electrification during contact irritates the nerves of the animal, leads muscles in motion, causes a feeling of sour taste at the tip of the tongue placed between stanic paper and a silver spoon, with silver and tin contact. Thus, Volta considers the causes of "galvanism" by physical, and physiological actions are one of the manifestations of this physical process. If briefly formulate on modern language Thought of Volta, it comes down to the following: the electroplane opened the physiological effect of electric current.

Naturally, the controversy broke out between the electroplating and Volta. Galvani for the proof of their rightness tried to completely exclude physical reasons. Volta, on the contrary, completely eliminated the physiological objects, replacing the frog foot with its electrometer. February 10, 1794 he writes:

"What do you think about the so-called animal electricity? As for me, I have long been convinced that all action arises originally due to the touch of metals to any wet body or to the water itself. By virtue of such contact, the electric fluid is chasing this wet body or into water from the metals themselves, from one more, from the other less (most of the zinc, least of the silver). When establishing a continuous message between the appropriate conductors, this fluid performs a permanent cycle. "

Instruments Volta.

This is the first description of the closed electrical circuit. If the chain is broken and in the place of the break insert as a connecting link is a viable nerve frog, "the muscles controlled by such nerves begin to shrink, as soon as the circuit of the conductors is closed and appears electricity" As you can see, Volta is already using such a term as a "closed electrical circuit". It shows that the presence of current in the closed chain can be detected and taste sensationsIf you enter a tip of the tip in the chain. "And these sensations and movements are the stronger, the further one from each other applied two metal in that row, in which they are delivered here: zinc, tin foil, ordinary tin in plates, lead, iron, brass and various quality Bronze, copper, platinum, gold, silver, mercury, graphite. This is the famous "Volta series" in his first sketch.

Volta split conductions into two classes. To the first one, he took the metals to the second-liquid conductors. If you make a closed chain of heterogeneous metals, then the current will not be a consequence of the Volta law for contact stresses. If "the second-class conductor is in the middle and comes into contact with two conductors of the first class of two different metals, then the electric current of one or another direction arises.

It is quite natural that this is exactly the honor of creating the first generator of electric current, the so-called Voltov Post (Volta himself called its "electric body"), which had a huge influence not only on the development of the science of electricity, but also for the entire history of human civilization. Volta pillar announced the occurrence of a new era - the era of electricity.

Electriform Volta.

The Triumph of the Voltov pillar provided the unconditional victory of Volta over the galvana. The story went wisely, determining the winner in this dispute, in which both parties were right, each from their point of view. "Animal electricity" really exists, and electrophysiology, the father of which was Galvani, is now occupied by an important place in science and practice. But during the Galvania, electrophysiological phenomena has not yet matured for scientific analysis, and the fact that Volta turned the opening of the galvana to the new way was very important for young electric science. By excluding the life is the most difficult phenomenon of nature from the science of electricity, giving physiological actions only the passive role of the reagent, Volta provided the rapid and fruitful development of this science. This is his immortal merit in the history of science and humanity.

Heinrich Rudolf Hertz, inventor "Vibrator Hertz"

Heinrich Rudolf Hertz (1857-1894) Born on February 22 in Hamburg, in the family of a lawyer, who later became a senator. Hertz studied perfectly and was unsurpassed by the student. He loved all objects, loved to write poems and work on the lathe. Unfortunately, all his life, Hertz prevented weak health.

In 1875, after the end of the gymnasium, Hertz enters Dresden, and then to the Munich Higher Technical School. The case went well until the subjects were studied general character. But as soon as specialization began, Hertz changed its decision. He does not want to be a narrow specialist, he rifles to scientific work And enters the University of Berlin. Hertz was lucky: Helmholz turned out to be his immediate mentor. Although the famous physicist was a commitment to the theory of long-range, but as a true scientist, he unconditionally admitted that the ideas of Faraday - Maxwell about the closest and physical field give excellent agreement with the experiment.

After hitting the University of Berlin, Hertz was striking in physical laboratories. But only those students who dealt with the competition tasks were allowed to work in the laboratories. Helmholz offered hertnts to the task from the field of electrodynamics: whether the electric current of the kinetic energy Helmgoltz wanted to send the strength of Hertz to the electrodynamics region, considering it the most confusing.

Hertz is adopted for solving the task, calculated for 9 months. He produces appliances and distributes them. When working on the first problem, the features of the researcher were immediately revealed: persistence, rare hardworking and art of the experimenter. The task was solved for 3 months. The result, as expected, was negative. (Now we are clear that the electric current, which is a directional movement electrical charges (electrons, ions), has kinetic energy. In order for the hertz to detect it, it was necessary to increase the accuracy of his experiment in thousands of times.) The result was coincided with the point of view of the Helmholtz, although erroneous, but in the abilities of the young hertz he was not mistaken. "I saw that I was dealing with a student of completely unusual dating," he noted later. The work of Hertz was awarded award.

Returning after the summer holidays of 1879, Hertz achieved permission to work on another topic:<0б индукции во вращающихся телах«, взятой в качестве докторской диссертации. Это была теоретическая работа. Он предполагал завершить ее за 2-3 месяца, защитить и получить поскорее звание доктора, хотя университет еще не был закончен. Работая с большим подъемом и воодушевлением, Герц быстро закончил исследование. Зашита прошла успешно, и ему присудили степень доктора с «отличием» - явление исключительно редкое, тем более для студента.

From 1883 to 1885, Hertz headed the Department of Theoretical Physics in the provincial town of Kiel, where there was no physical laboratory at all. Hertz decided to engage in theoretical issues here. It adjusts the system of electrodynamics equation of one of the bright representatives of the long-range neiman. As a result of this work, Hertz wrote his system of equations from which the Maxwell equations were easily obtained. Hertz is disappointed, because he tried to prove the universality of electrodynamic theories of representatives of long-range representatives, and not the theory of Maxwell. "This conclusion cannot be considered the exact proof of the Maxwellian system as the only possible," he does for himself, essentially soothing withdrawal.

In 1885, Hertz adopts an invitation to a technical school in Karlsruhe, where its famous experiments will be carried out on the spread of electric power. Back in 1879, the Berlin Academy of Sciences put the task: "Show experimentally, the presence of any connection between the electrodynamic forces and dielectric polarization of dielectrics". The preliminary calculations of Hertz showed that the expected effect will be very small even under the most favorable conditions. Therefore, apparently, he refused this work in the fall of 1879. However, he did not stop thinking about the possible ways to solve it and came to the conclusion that there were high-frequency electrical fluctuations for this.

Hertz carefully studied everything that was known by this time about electrical fluctuations and in theoretical, and in experimental plans. Finding in the physical office of technical school a couple of induction coils and spending lecture demonstrations with them, Hertz found that with their help it was possible to get fast electrical oscillations with a period of 10 -8 C. As a result of the experiments, the hertz created not only a high-frequency generator (source of high-frequency oscillations) , but also the resonator is the receiver of these oscillations.

The hertz generator consisted of an induction coil and the wires attached to it forming the discharge gap, the resonator - from the wire of the rectangular shape and two balls at its ends forming also the discharge gap. As a result of the experiments conducted, Hertz found that if high-frequency oscillations will occur in the generator (in its discharge gap, the spark surrounds), then in the discharge gap of the resonator, removed from the generator even 3 m , Also will slip small sparks. Thus, the spark in the second chain arose without any direct contact with the first chain. What is the mechanism of its transfer or this is an electrical induction, according to the theory of the Helmholtz, or an electromagnetic wave, according to the Maxwell theory in 1887, Herz still says nothing else about electromagnetic waves, although he has already noticed that the influence of the generator on the receiver is especially strong in the case of resonance (The oscillation frequency of the generator coincides with its own frequency of the resonator).

Having numerous experiments with different mutual positions of the generator and receiver, HERC concludes the existence of electromagnetic waves propagating at the final rate. Will they behave like light and hertz spend a thorough check of this assumption. After studying the laws of reflection and refraction, after establishing polarization and measuring the speed of electromagnetic waves, he proved their full analogy with light. All this was set out in the work "On the Rays of Electric Force", released in December 1888. This year is considered a year of opening electromagnetic waves and experimental confirmation of Maxwell's theory. In 1889, speaking at the congress of German naturalists, Hertz said: "All these experiences are very simple in principle, nevertheless they entail the most important investigations. They ruin all the theory, which believes that the electrical forces jump space instantly. They mean the brilliant victory of the theory of Maxwell. How unlikely it seemed earlier her leen on the essence of light, it is so difficult now not to divide this alert. "

The stress work Hertz did not go unpunished for his already weak health. At first they refused the eyes, then sick ears, teeth and nose. Soon the overall infection of blood began, from which the scientist Heinrich Hertz already died in his 37 years.

Hertz completed a huge work started by Faraday. If Maxwell transformed the pharade submission to mathematical images, then the hertz turned these images to visible and audible electromagnetic waves, which became an eternal monument to him. We remember the city of Hertz, when we listen to the radio, watch TV when you rejoice in the post of TASS about new launches of spacecraft with which a steady connection is supported using radio waves. And it was not by chance that the first words transmitted by the Russian physicist A. S. Popov in the first wireless communications were: "Heinrich Hertz."

"Very fast electrical oscillations"

Henry Rudolf Hertz (Heinrich Rudolf Hertz), 1857-1894

In the period from 1886 to 1888, the hertz in the corner of his physical office in the Karlsruhe Polytechnic School (Berlin) explored the radiation and reception of electromagnetic waves. For these purposes, he came up with and constructed his famous emitter of electromagnetic waves, named afterwards the "hertz vibrator". The vibrator was two copper rods with plated beads planned at the ends and one large zinc sphere or a square plate playing the role of the capacitor. Between the balls remained a gap - spark gap. The ends of the secondary winding of the Rumcorph - Low Voltage DC converter to the alternating current of high voltage were attached to the copper rods. Under the impulses of alternating current between the balls, the sparks slipped and electromagnetic waves were emitted into the surrounding space. The movement of spheres or plates along the rods was adjusted inductance and capacitance of the chain, determining the wavelength. To capture the emitted waves, the hertz came up with the simplest resonator - a wireless ring or a rectangular impaired frame with the same brass balls at the ends and adjustable spark gap.

Vibrator Hertz

The concept of vibrator hertz was introduced, the working circuit of the vibrator hertz is given, the transition from the closed contour to the electric dipper is considered.

Through the vibrator, the resonator and reflective metal screens, the hertz proved the existence of the predicted Maxwell electromagnetic waves propagating in the free space. He proved their identity with light waves (similarity of reflection, refraction, interference and polarization phenomena) and managed to measure their length.

Thanks to his experiments, Hertz came to the following conclusions: 1 - waves Maxwell "Synchronous" (the validity of the Maxwell theory, that the speed of radio wave is equal to the speed of light); 2 - You can transmit the energy of the electric and magnetic field without wires.

In 1887, at the end of the experiments, the first article of Hertz "On very fast electrical oscillations" was published, and in 1888 - even more fundamental work "On electrodynamic waves in the air and their reflection".

Hertz believed that his discoveries were not practical than Maxwellov: "This is absolutely useless. This is only an experiment, which proves that Maestro Maxwell was right. We only have mysterious electromagnetic waves that cannot see the eye, but they are. " "And what's next?" - asked him one of the students. Hertz shrugged, he was a modest person, no complaints and ambitions: "I guess - nothing."

But even on theoretical level, the achievements of Hertz were immediately marked by scientists as the beginning of a new "electric era".

Heinrich Hertz died at the age of 37 years in Bonn from blood infection. After the death of Hertz in 1894, Sir Oliver Lodge noticed: "Hertz did something that famous English physicists could not make. In addition, he confirmed the truth of the theorem Maxwell, he did it with a discouraging modesty. "

Eduard Eugene Desair Branle, the inventor of the "Sensor Branle"

The name of Edward Bunly is not particularly known in the world, but in France, it is considered one of the most important investors in the invention of the radio telegraph communications.

In 1890, Professor of Physics of the Paris Catholic University, Edward Bunly, became seriously interested in the possibility of using electricity in therapy. In the morning, he was heading to Paris hospitals, where he conducted therapeutic procedures with electric and induction currents, and during the day the behavior of metal conductors and galvanometers was investigated when exposed to electric charges in its physical laboratory.

The device that Branley brought fame was "glass tube freely filled with metal sawdust" or "Sensor Branle". When the sensor is turned on in the electrical circuit containing the battery and the galvanometer, it worked as an insulator. However, if at some distance from the scheme there was an electric spark, the sensor started to carry out the current. When the tube was slightly shaken, the sensor again became an insulator. The reaction of the Bunly sensor on the spark was observed within the laboratory premises (up to 20 m). The phenomenon was described by Bunly in 1890.

By the way, such a method for changing the resistance of sawdust, only coal, during the passage of electric current, until recently used everywhere (and in some homes it is also understood) in microphones of telephone sets (the so-called "coal" microphones).

According to historians, Bunly never thought about the possibility of transmitting signals. He was interested in the mainly parallel between medicine and physics and sought to offer the medical interpretation of the conductivity of the nerve, modeled with the help of pipes filled with metal sawdust.

For the first time publicly demonstrated the connection between the conductivity of the Branle sensor and the electromagnetic waves of the British physicist Oliver Lodge.

Lavoisier Antoine Laurent, calorimeter inventor

Antoine Laurent Lavoisier was born on August 26, 1743 in Paris in a lawyer's family. He received an initial education in Mazarin College, and in 1864 he graduated from the Faculty of Law of the University of Paris. Already during training at the University of Lavoisier, in addition to jurisprudence, it was thoroughly engaged in natural and accurate sciences under the guidance of the best Paris professors of that time.

In 1765, Lavoisier presented the topic of the topic specified by the Paris Academy of Sciences - "On the best way to illumine the streets of the Big City". When performing this work, the extraordinary perseverance of the Lavoisier in the pursuit of the intended goal and accuracy in surveys - the merits that make up a distinctive feature of all his works. For example, in order to increase the sensitivity of your vision to weak changes in the power of light, Lavoisier spent six weeks in the dark room. This work of Lavoisier was awarded the Golden Medal Academy.

In the period 1763-1767 Lavoisier makes a number of excursions with the most famous geologist and Mineralog Gattar, helping the latter in the compilation of the Mineralogical Map of France. Already these first works of Lavoisier opened the doors of the Paris Academy in front of him. On May 18, 1768, he was elected to the Academy of Adjunct in Chemistry, in 1778 he became a valid member of the Academy, and since 1785 he consisted of its director.

In 1769, Lavoisier joined the company of otkupov - the organization from forty major financiers, in exchange for immediate contribution to the treasury a certain amount received the right to collect state indirect taxes (on salt, tobacco, etc.). Being a spider, Lavoisier has acquired a huge fortune, part of which spent on scientific research; However, it was the participation in the company of otkupov, it became one of the reasons why Lavoisier was in 1794 sentenced to the death penalty.

In 1775, Lavoise becomes director of gunpowder and Selitra. Thanks to the energy of the Lavoise, the production of powder in France by 1788 more than doubled. Lavoisier organizes expeditions to find saltiodic fields, conducts research related to cleaning and analyzing SELITRA; Takes to clean the nitrate, developed by Lavoisier and Bom, reached our time. Powder Lavoisier ruled until 1791. He lived in the Powder Arsenal; Here, a wonderful chemical laboratory created by him on its own funds was also placed, from which almost all chemical works came out, desony for his name. Lavoisier laboratory was one of the main scientific centers of Paris of the time.

In the early 1770s. Lavoisier starts systematic experimental work on the study of combustion processes, as a result of which it comes to the conclusion about the insolvency of the theory of phlogiston. Having received in 1774 (following K.V.Shelele and J.prirchi) oxygen and chances to realize the importance of this discovery, the Lavoisier creates the oxygen theory of burning, which sets out in 1777 in 1775-1777. Lavoisier proves the complex composition of air consisting, in its opinion, from "clean air" (oxygen) and "suffocating air" (nitrogen). In 1781, together with mathematician and chemist, the complex composition of water also proves, establishing that it consists of oxygen and "fuel air" (hydrogen). In 1785, they also synthesize water from hydrogen and oxygen.

The doctrine of oxygen, as the main burning agent, was at first it was very hostile. Famous French Chemist Mactene makes fun of a new theory; In Berlin, where the memory of the creator of the phlogiston theory of the staff is especially honored, the works of Lavoisier was even devoted to burning. Lavoisier, however, not spending time for the controversy with the view, the failure of which he felt, step by step persistently and patiently established the foundations of his theory. Only thoroughly after studying the facts and finally finding out its point of view, the Lavoisier in 1783 opened openly with the criticism of the teaching about the phlogistone and shows its preciousness. The establishment of the composition of the water was a decisive blow for the theory of phlogistone; Supporters began to move onto the side of the Lavoisier teachings.

Relying on the properties of oxygen compounds, Lavoisier first gave the classification of "simple bodies", known at the time in chemical practice. The concept of Lavoisier about elementary bodies was purely empirical: elementary lavanise considered those bodies that could not be decomposed on simpler composite parts.

The basis for its classification of chemicals together with the concept of simple bodies, served the concepts of "oxide", "acid" and "salt". Lavoisier oxide is a compound of metal with oxygen; Acid is a compound of a non-metallic body (for example, coal, sulfur, phosphorus) with oxygen. Organic acids are acetic, oxal, wine, and others. - Lavoisier considered as compounds with oxygen of various "radicals". Salt is formed by an acid compound with base. This classification, as soon as further studies have shown, was narrow and therefore incorrect: some acids, such as blue acid, hydrogen sulfide, and the salts correspond to them, did not fit under these definitions; Acid Salt Lavoisier considered the compound of oxygen with an unknown radical, and chlorine considered as a compound of oxygen with hydrochloric acid. Nevertheless, it was the first classification, which gave the opportunity with great simplicity to observe the range of those known at the time in the chemistry of tel. She gave a lavanise opportunity to predict the complex composition of such bodies as lime, barite, caustic alkali, boric acid, etc., who were considered elementary to him.

In connection with the refusal of phlogiston theory, it was necessary to create a new chemical nomenclature, which was based on a classification, this lavanise. The basic principles of the new nomenclature of Lavoisier develops in 1786-1787. Together with C.L.Berrtoll, L. B. Giton de Morso and A.F.Furkrua. The new nomenclature has made great simplicity and clarity in a chemical language, clearing it from complex and tangled terms that were tested by alchemy. Since 1790, Lavoisier also participates in the development of a rational system of measures and scales - metric.

The subject of study of the Lavoisier was and thermal phenomena, closely related to the combustion process. Together with Laplas, the future Creator of "Heavenly Mechanics", Lavoisier gives the beginning of calorimetry. They create ice calorimeterWith which the heat capacity of many bodies and heat is measured, released under various chemical transformations. Lavoisier and Laplace in 1780 establish the basic principle of thermochemistry, formulated by them in the following form: "Any thermal changes that some material system experiences, change its condition, occur in the order of the opposite when the system returns to its original state."

In 1789, Lavoisier published a textbook "Elementary Chemistry Course", entirely based on the oxygen theory of combustion and a new nomenclature, which became the first textbook of new chemistry. Since the French revolution began in the same year, the coup, committed in the chemistry of the Lavoisier, was customary to be called a "chemical revolution".

The Creator of the Chemical Revolution, Lavoisier became, however, the victim of the revolution is social. At the end of November 1793, the former participants in the sputter were arrested and destroyed by the court of the revolutionary tribunal. Neither the petition from the "Testing Bureau of Arts and Crafts" nor all the well-known merits in front of France nor the scientific glory saved the Lavoisier of death. "The Republic does not need scientists," the chairman said, the Kofinal Tribunal in response to the petition of the Bureau. Lavoisier was accused of participating in the conspiracy with the enemies of France against the French people who had the goal to kidnap the nation with the huge amounts necessary for the war with despoty, "and was awarded to death. "The executioner was quite a moment to cut off this head," said the famous mathematician Lagrange on the execution of Lavoisier, - "But there will be few centuries to give another the same ..." In 1796, Lavoise was posthumously rehabilitated.

Since 1771, Lavoise was married to his daughter his comrade for the benefit. In his wife, he found an active career in his scientific papers. She led his laboratory magazines, translated from English scientific articles for him, drawing and engraving the drawings for his textbook. By the death of Lavoisier, his wife was released in 1805 to marry the famous physics of Rumford. She died in 1836 at the age of 79.

Pierre Simon Laplace, Calorimeter Inventor, Barometric Formula

French astronomer, mathematician and physicist Pierre Simon de Laplace born in Bamon-An-Oh, Normandy. He studied at the Bennedctic School, from which came out, however, a convinced atheist. In 1766, Laplace arrived in Paris, where Zh. D'Albert in five years helped him get a place of professor of military school. Operations participated in the reorganization of the Higher Education System in France, in the creation of normal and polytechnic schools. In 1790, Laplace was appointed Chairman of the Chamber of Measures and Libra, led the introduction of a new metric system of measures. Since 1795, as part of the leadership of the Longitude Bureau. Member of the Parisian An (1785, Adjunct since 1773), Member of the French Academy (1816).

The scientific heritage of Laplace refers to the field of heavenly mechanics, mathematics and mathematical physics, the fundamental are the works of Laplace on differential equations, in particular by integrating the method of "cascades" of equations with private derivatives. Laplas entered ball functions have a variety of applications. The Laplas algebra has an important theorem on the submission of identifiers by the amount of the works of additional minors. To develop the mathematical theory of probabilities created by them, Laplace introduced the so-called production functions and was widely used the transformation that bears his name (Laplace transformation). The theory of probabilities was the basis for studying all sorts of statistical patterns, especially in the field of natural science. Before him, the first steps in this area were made by B. Pascal, P. Farm, Ya. Bernoulli, and others. Laplace brought their conclusions to the system, improved the methods of evidence, making them less cumbersome; Proved the theorem that begins his name (Laplace Theorem), developed the theory of errors and the method of smallest squares, allowing to find the most sensitive values \u200b\u200bof the measured values \u200b\u200band the degree of reliability of these calculations. The classic Laplace work "Analytical theory of probabilities" was published three times with his life - in 1812, 1814 and 1820; As an introduction to the latest editions, the work of the "Experience of the Philosophy of Probability Theory" (1814) was placed, in which the main provisions and the importance of the theory of probability are explained in popular form.

Together with A. Lavoisier in 1779-1784. Laplace was engaged in physics, in particular the issue of hidden warmth of melting bodies and works with them ice calorimeter. To measure the linear expansion of the bodies, they first applied the visual tube; We studied the burning of hydrogen in oxygen. Laplace actively opposed the erroneous hypothesis about the phlogistone. Later again returned to physics and mathematics. He published a number of works on the theory of capillarity and established a law that brings his name (Laplace Act). In 1809, Laplas took up acoustics issues; He brought the formula for the speed of propagation of sound in the air. Laplas belong barometric formula To calculate the change in the density of air with a height above the surface of the Earth, taking into account the effect of air humidity and the change in the acceleration of free fall. He was also engaged in geodesy.

Laplace developed the methods of heavenly mechanics and completed almost everything that it failed to predecessors in explaining the movement of the television of the solar system based on the law of Newton's World Act; He managed to prove that the law of world gravity fully explains the movement of these planets, if they submit their mutual perturbations in the form of a number. He also proved that these perturbations are periodic. In 1780, Laplace proposed a new way to calculate the orbits of celestial bodies. Laplace's studies have proven stability of the solar system for a very long time. Next, Laplace came to the conclusion that the Saturn Ring cannot be solid, because In this case, it would be unstable and predicted the opening of the strong compression of Saturn at the poles. In 1789, Laplace considered the theory of the movement of the satellites of Jupiter under the action of mutual perturbations and attraction to the Sun. He received the complete consent of the theory with observations and established a number of laws of these movements. One of the main merits of Laplas was the discovery of the reason for the acceleration in the Moon's movement. In 1787, he showed that the average motion rate of the moon depends on the eccentricity of the earth orbit, and the latter changes under the action of attraction of the planets. Laplace proved that this indignation is not a century, but long-period and that subsequently the moon will move slowly. By inequalities in the movement of Laplace, Laplace determined the magnitude of the compression of the Earth in the poles. He also owns the development of dynamic theory of tides. The heavenly mechanics are largely owned by the works of Laplas, which are summarized in the classical essay "Treatise on Heavenly Mechanics" (t. 1-5, 1798-1825).

The cosmogonic Laplace hypothesis had a huge philosophical meaning. It is presented to them in the appendix to his book "Statement of the World System" (t. 1-2, 1796).

In philosophical views, Laplace was adjacent to French materialists; Laplas Napoleon's response is known, which in his theory about the origin of the solar system he did not need a hypothesis about the existence of God. The limitations of mechanistic materialism Laplace manifested itself in an attempt to explain the whole world, including physiological, mental and social phenomena, from the point of view of mechanistic determinism. His understanding of determinism Laplace considered as a methodological principle of building any science. A sample of the final form of scientific knowledge of Laplace saw in heavenly mechanics. Laplasian determinism has become a none denotation of the mechanistic methodology of classical physics. The materialistic worldview of Laplas, brightly spoken in scientific works, contrasts with its political instability. With any political coup, Laplace moved to the side of the winners: at first he was the Republican, after the arrival of Napoleon - the Minister of the Interior; Then he was appointed a member and vice-chairman of the Senate, when Napoleon received the title of the Empire Count, and in 1814 he filed his voice for the lowland of Napoleon; After the restoration of Bourbonov received Parity and the title of Marquis.

Oliver Joseph Lodge, coherer inventor

Among the main merit of the Lodge in the context of the radio, it should be noted its improvement of the radio wave sensor Branle.

The coherer of the lodge, first demonstrated before the audience of the Royal Institute in 1894, made it possible to take the signals of the Morse code transferred by radio waves and allowed them to write them to the registering apparatus. This allowed the invention to soon become a standard device of wireless telegraph devices. (The sensor was separated only in ten years, when magnetic, electrolytic and crystalline sensors are developed).

No less important is the work of the lodge in the field of electromagnetic waves. In 1894, London Electrician's lines arguing about the meaning of the openings of Hertz, described its experiments with electromagnetic waves. He commented on the phenomenon discovered by the phenomenon of resonance or settings:

... Some schemes are "vibrating ... they are capable of maintaining fluctuations in them for a long period, while in other oscillation schemes quickly fade. The athletic type receiver will respond to the waves of any frequency, as opposed to the receiver based on a constant frequency, which reacts only to the waves with the frequency of its own oscillations.

The Lodge found that the hertz vibrator "radiates very powerful", but "due to radiation of energy (into space), its oscillations are quickly faded, so it must be configured in accordance with the receiver."

August 16, 1898 Lodge received Patent No. 609154, which was proposed "to use a customizing induction coil or antenna contour in wireless transmitters or receivers, or in both devices." This "configuring" ("Syntonic") patent was of great importance in the history of the radio, since it described the principles of setting up to the desired station. March 19, 1912 This patent was acquired by Marconi.

Subsequently, Marconi said that the lodge said:

He (Lodge) is one of our largest physicists and thinkers, but its work in the field of radio is particularly significant. From the very first days, after experimental confirmation of the Maxwell's theory regarding the existence of electromagnetic radiation and its distribution through space, very few people had a clear understanding of the at least of this one of the most hidden secrets of nature. Sir Oliver Lodge possessed this understanding to a much greater degree than any other of his contemporaries.

Why did the lodge invented the radio? He himself explained this fact so:

I was too busy with work to take for the development of the telegraph or any other direction of technology. I did not have a sufficient understanding of feeling how much it would be extraordinary important for the fleet, trade, civil and military communications.

For the contribution of the development of science in 1902, King Edward VII dedicated the lodge in the knights.

Interesting and mysterious further fate of Sir Oliver.

After 1910, he was carried away by spiritualism and became a fierce supporter of communication ideas with the dead. He was occupied by the issues of communication of science and religion, telepathy, manifestations of the mysterious and unknown. In his opinion, the easiest way to communicate with Mars will be moving along the sugar of giant geometric figures. At the age of eighty, the Lodge announced that he would try to contact the world of living after his death. He conveyed a sealed document for storing into the English society of mental research, in which, according to him, contained the text of the message that he will transmit from the next world.

Luigi Galvani, Galvanometer inventor

Luigi Galvani was born in Bologna on September 9, 1737 he studied theology at first, and then medicine, physiology and anatomy. In 1762, he was already a teacher of medicine in the University of Bologna.

In 1791, the famous discovery was described in the Treatise on Electricity for Muscular Movement. The phenomena, open electroplants, for a long time in textbooks and scientific articles were called "Galvanism". This term dynamine is stored in the name of some devices and processes. Helvani himself describes his discovery as follows:

"I cut and disperse a frog ... and, having in mind completely different, placed it on the table on which there was an electric car ..., with a full disagreement from the conductor of the latter and at a fairly large distance from it. When one of my helpers with the edge of the scalpel accidentally, very easily touched the inner femoral nerves of this frog, then immediately all the limb sodes began to shrink so much that they seemed to have fallen into the strongest tonic convulsions of the other of them, who helped us in electricity experiences, noticed It seemed that it would be possible when a spark was extracted from the car conductor ... Surprised by a new phenomenon, he immediately turned my attention to him, although I was completely different and was absorbed by my thoughts. Then I left the incredible diligence and passionate desire to explore this phenomenon and take into the light what was in it hidden. "

This is a classic description of the description has been repeatedly reproduced in historical works and gave rise to numerous comments. Galvani honestly writes that the phenomenon first noticed not he, but his two assistants. It is believed that "other of those present", indicating that the abbreviation of the muscles comes when surrounding the spark in the car, his wife Lucia was. Galvania was busy with his thoughts, and at this time someone began to rotate the handle of the car, someone touched the "easily" scalpel to the drug, someone noticed that the muscle contraction occurs when there is a spark. So in the chains of accidents (all the actors were unlikely to deal with each other) Born the great discovery. Galvani distracted from their thoughts, "he himself, began to touch the scalpel's edge, then another female nerve, while one of those present removed the spark, the phenomenon came in exactly the same way."

As we can see, the phenomenon was very difficult, three components came into effect: the electric machine, scalpel, the preparation of the frog paws. What is essential? What happens if one of the components is not? What is the role of sparks, scalpel, frogs? All these questions and tried to get the answer of Galvana. He put numerous experiences, including on the street during a thunderstorm. "And now, noticing that the prepared frogs that were suspended on the iron lattice surrounding the balcony of our house, with the help of copper hooks, stuck in the spinal cord, fell into ordinary cuts not only in a thunderstorm, but sometimes also with a calm and clear sky. I decided that these cuts are caused by changes occurring during the day in atmospheric electricity. " Galvani describes further how it expects these abbreviations in vain. "Tired, finally, in vain expectation, I began to press copper hooks, stuck in the spinal cord, to the iron grille" and here found the desired abbreviations that took place without any changes in the state of the atmosphere and electricity.

Galvani moved experience in the room, placed the frog on the iron plate, to which the hook spent across the spinal cord was immediately appeared muscle contraction. That was a decisive discovery.

Galvania realized that something new was opened before him, and decided to carefully examine the phenomenon. He felt that in such cases "it is easy to make a mistake with research and consider it seen and found what we wish to see and find", in this case, the effect of atmospheric electricity he suffered a drug "In a closed room, placed on the iron plate and began to press it Conducted through the spinal cord hook. " At the same time, "the same abbreviations appeared, the same movements." So, there is no electric car, no atmospheric discharges, and the effect is observed, as before, "says," Hello writes, "there was a considerable surprise in us and began to initiate some suspicion of electricity to the animal inherent in us." To verify the justice of such "suspicion", the galvana makes a series of experiments, including a spectacular experience when the suspended foot, touching the silver plate, is shrinking, it is pressed up, then falls, reducing again, etc. "So this foot, "He writes a galvana," to considerable admiration for the observing behind her, it seems to compete with some electric pendulum. "

The suspicion of the galvanic turned into confidence: the frog's foot began to be a carrier of the "animal electricity", like a charged Leiden Bank. "After these discoveries and observations, it seemed to me possible without any delay to conclude that this dual and opposite electricity was in the animal preparation." He showed that positive electricity is in the nerve, negative - in the muscle.

It is quite natural that the physiologist of Galvani came to the conclusion about the existence of an "animal electricity". The whole setting of experiments pushed to this conclusion. But the physicist who believed first to the existence of an "animal electricity", soon came to the opposite conclusion about the physical cause of the phenomenon. This physicist was the famous compatriot of Galvani Alessandro Volta.

John Ambroz Fleming, Valnera Inventor

English Engineer John Fleming made a significant contribution to the development of electronics, photometry, electrical measurements and radio telegraph communications. The most famous of its invention of the radio detector (rectifier) \u200b\u200bwith two electrodes, which he called the thermoelectronic lamp, also known as a vacuum diode, kenotron, electronic lamp and a lamp or a flopping diode. This device patented in 1904 was the first electronic radio wave detector, converting AC radio signals to a constant current. The opening of Fleming was the first step in the era of lamp electronic technology. Epoch, which lasted without a small until the end of the 20th century.

Fleming studied at the University College in London and Cambridge in the Great Maxwell, for many years he worked as a consultant in London companies Edison and Marconi.

There was a very popular teacher at a university college and the first one who was awarded the title of professor electrical engineering. It was the author more than a hundred scientific articles and books, including those popular: "Principles of Electric Wave Telegraph" (1906) and "Dissemination of electric currents in telephone and telegraph wipes" (1911), which many years have been leading books on this topic. In 1881, when electricity began to attract universal attention, Fleming entered the service of Edison in London to the position of an electrician engineer, which was held almost ten years.

It was natural that the work of Fleming for electricity and telephony should be sooner or later to bring it into a nascent radio engineering. For more than twenty-five years, he served as a scientific adviser to Marconi and even participated in the creation of the first transatlantic station.

For a long time, disputes were not poisoned about the wavelength, on which the first transatlantic transmission was carried out. In 1935, in his memoirs, Fleming commented on this fact so:

"In 1901, the wavelength of the electromagnetic radiation was not measured, because I still did not invent voltaire (invented in October 1904). The height of the antenna suspension in the first embodiment was 200 feet (61 m). In series with the antenna, we plugged the transformer coil or "JigGeroo" (transformer attempting oscillations). According to my estimates, the initial wavelength should have been at least 3,000 feet (915 m), but later it was much higher.

At that time, I knew that the diffraction, bending of the waves around the Earth, would increase with an increase in the wavelength and after the first success constantly urged Marconi to increase the wavelength, which was done when commercial programs began. I remember that I developed special waves to measure waves about 20,000 feet (6096 m). "

Triumph Polluts belonged to Marconi, and Fleming's fame brought a "small electric incandescent lamp" - a diode of a fling. He himself described this invention so:

"In 1882, as an adviser to Edison (" Edison Electric Light Company of London ") for electricity, I solved numerous problems with incandescent lamps and began to study the physical phenomena that occur in them by all technical means available at my disposal. Like many others, I noticed that the threads of incandescent easily broke with small blows and after the lamp of the lamps, their glass flasks changed color. This glass change was so familiar what was taken by all as a given. It seemed a trifle to pay attention to it. But in science, all the little things should be taken into account. Little things today, tomorrow can be of great importance.

Canding the question why the flask of incandescent lamps dark, I began to explore this fact and found that a glass strip had had a glass that did not change the color in many disturned lamps. It seems that someone took a wiggy flask and washed a raid, leaving a clean narrow strip. I found that lamps with these strange, sharply outlined clean areas were covered with precipitated carbon or metal. A pure strip was certainly U-shaped, repeating the shape of the coal thread, and just on the opposite side of the flask side.

It became obvious to me that the undisturbed part of the thread acted as the screen, leaving the very characteristic strip of pure glass, and that charges of the heated incandescent thread bombard the walls of the lamp of carbon molecules or evaporated metal. My experiments in late 1882 and early 1883 proved that I was right. "

Edison also noticed this phenomenon, by the way, called the "Edison effect", but could not explain his nature.

In October 1884, the research "Edison effect" was engaged in William. He decided that this was due to the emission of coal molecules from incandescent threads in straight directions, thus confirming my initial opening. But she, like Edison, also did not ensure to the truth. He did not explain the phenomenon and did not strive to apply it. The "Effect Edison" remained a secret incandescent lamp.

In 1888, Fleming received several special carbon incandescent carbon lamps made in England Edison and Joseph Suban and continued experiments. He put a negative tension to the coal filament and noticed that the bombardment of charged particles ceased.

When changing the position of the metal plate, the bombing intensity changed. When, instead of the plate in the flask, a metal cylinder was placed, located around the negative contact of the thread without contact with it, the galvanometer recorded the greatest current.

Fleming became apparent that the metal cylinder "captured" the charged particles that emitted the thread. Having thoroughly examining the properties of the effect, it found that the combination of the thread and plate, called an anode, could be used as a rectifier of variable currents not only industrial, but also high frequency used in the radio.

The work of Fleming in Marconi, allowed him to carefully familiarize himself with the capricious coherer used as a wave sensor. In search of the best sensor, he tried to develop chemical detectors, but at what time a thought came to him: "Why do neither try the lamp?"

Fleming so described his experiment:

"It was approximately 5 pm when the device was completed. I certainly wanted to check it in action. In the laboratory, we installed two of these schemes at some distance from each other, and I launched the oscillations in the main chain. To my admiration I saw that the arrow galvanometer showed a stable constant current. I realized that we got in this specific form of the electrical lamp, solving the problem of straightening high-frequency currents. The "missing detail" in the radio was found and it was an electric lamp! "

At first he collected a vibrational contour, with two ledden jars in a wooden case and with an induction coil. Then another scheme, which included the electronic lamp and the galvanometer. Both schemes were configured to the same frequency.

I immediately understood that the metal plate should be replaced with a metal cylinder closing the entire thread to "collect" all emitted electrons.

I have in stock there were many coal incandescent bulbs with metal cylinders, and I began to use them as high-frequency rectifiers for a radio telegraph connection.

I called this device by a vibrational lamp. She was immediately found applied. Galvanometer Replaced the usual phone. The replacement that could be done at that time, taking into account the development of technology, when spark communication systems were used everywhere. In this form, my lamp was widely used by Marconi as a wave sensor. November 16, 1904 I filed a patent application in the UK.

The invention of the vacuum diode Fleming was awarded a set of honors and awards. In March 1929, he was dedicated to the knights for "invaluable contribution to science and industry"

In 1795, a law on new measures and scales was adopted in France, which set a single length of length - meterequal to the ten-million part of a quarter of the arc meridian passing through Paris. Hence the name of the system is metric.

A platinum rod one meter long and a very strange form was elected as a standal meter. Now the size of all lines, a length of one meter, had to correspond to this standard.

Units were installed:

- liter As a measure of the capacity of liquid and bulk bodies, equal to 1000 cubic meters. centimeters and accommodating 1 kg of water (at 4 ° heat Celsius),

- gram as a unit of weight (weight of pure water at a temperature of 4 degrees Celsius in the volume of cube with an edge of 0.01 m),

- aR as a unit of space (square square with a side of 10 m),

- second As a unit of time (1/86400 part of the average sunny day).

Later the main unit of mass became kilogram. The prototype of this unit served as a platinum giry, which was put under the glass flasks and fade the air - so that the dust would not fall and the weight did not increase!

The prototypes of the meter and kilogram today are stored in the national archive of France and are called the "archive meter" and "kilogram of the archive", respectively.

Different measures were before, but the important dignity of the metric measures was its decade, since the dolly and multiple units, according to the rules adopted, were formed in accordance with the decimal score with the help of decimal faults, which correspond to the Council of the Council, Santi, - Milli - Deck, - hecto- and kilo.

Currently, the metric system of measures is adopted in Russia and in most countries of the world. But there are other systems. For example, the English system of measures in which foot, pound and second are adopted for the main units.

Interestingly, in all countries there are familiar packs for different products and drinks. In Russia, for example, milk and juices are usually failed in liter packages. And large glass jars - all the tri-liter!

Remember: On professional drawings, the dimensions (sizes) of products are signed in millimeters. Even if it is very big products, like cars!

Volkswagen "Kadi".

Citroen "Burlingo".

Ferrari-360.

The international system of units is a structure based on the use of mass indicators in kilograms and lengths in meters. From its very occurrence, there were various options. The difference between them was to choose the main indicators. To date, many countries are used by the units of measurements in it elements are the same for all states (the exception is US, Liberia, Burma). This system is widely used in different spheres - from everyday life to scientific research.

Features

The metric measures system is an ordered set of parameters. This significantly distinguishes it from the previously used traditional methods for determining certain units. To refer to any value, the metric system measures uses only one basic indicator, the value of which may vary in multiple shares (it is achieved by the use of decimal dotted elements). The main advantage in this approach is the simpler use. This eliminates a huge number of different unnecessary units (feet, miles, inches and others).

Temporary parameters

For a long period, from a number of scientists, attempts were made to present time in metric units of measurement. It was proposed to divide the day into smaller elements - milli satellites, and the angles are 400-haired or receive a full turnover cycle for 1000 millipotes. Over time, due to the inconvenience, it was necessary to refuse this idea. Today, time in C is denoted by means of seconds (consist of milliseconds) and radians.

History of origin

It is believed that the modern metric system of measures was born in France. In the period from 1791 to 1795, in this country, the most important legislative acts were adopted. They were aimed at determining the status of a meter - one ten million dollars of 1/4 Meridian from the equator to the North Pole. July 4, 1837 adopted a special document. According to him, it was officially approved by the mandatory use of elements from which a metric system of measures was consisted, in all economic transactions carried out in France. In the future, the adopted structure began to spread to neighboring countries of Europe. Due to its simplicity and convenience, the metric system of measures gradually displaced the majority of the nationally used earlier. It is also permissible to use it in the United States and the UK.

Main values

For the length of the system, the founders of the system, as mentioned above, took the meter. The element of the mass was gram - the weight of one million m 3 of water during its standard density. For more convenient use of the units of the new system, the creators have come up with a way to make them more accessible - by manufacturing standards from metal. These models are made with the perfect accuracy of reproducing values. Where are the standards of the metric system, will be said below. In the future, when using these models, people realized that compare the desired importance with them is much easier and more convenient than, for example, with a quarter of the meridian. At the same time, determining the mass of the artistic body, it became obvious that it is much more convenient to evaluate it on the standard than according to the appropriate amount of water.

"Archive" samples

By the decision of the International Commission in 1872, it was adopted for the standard for measuring the length of a specially manufactured meter. At the same time, members of the Commission decided to take a special kilogram for the standard. It was made of platinum and iridium alloys. "Archive" meter and kilograms are on constant storage in Paris. In 1885, the 20th May, the representatives of the seventeen countries were signed a special convention. As part of it, the procedure for determining and using measurement standards in scientific research and works was regulated. To do this, they needed special organizations. These, in particular, include the International Bureau of Measures and Scales. Within the framework of the newly created organization, the development of mass samples and length began, with subsequent transmission of their copies to all participating countries.

Metric system of measures in Russia

The accepted samples used more and more countries. In the current conditions, Russia could not ignore the emergence of the new system. Therefore, law of July 4, 1899 (author and developer - D. I. Mendeleev) It was permitted to use in an optional manner. It became obligatory only after the adoption by the Provisional Government of the relevant Decree of 1917. Later, its use was enshrined by the decision of the USSR SCC from July 21, 1925. In the twentieth century, most countries moved to the measurements in the international system of SI units. It was designed and approved by the XI General Conference in 1960.

The collapse of the USSR coincided with the moment of the rapid development of computer and household appliances, the main production of which is concentrated in Asia countries. A huge part of goods of these manufacturers began to be imported into the territory of the Russian Federation. At the same time, Asian states did not think about the possible problems and inconvenience of their goods to the Russian-speaking population and supplied their products universal (in their opinion) instructions in English, using American parameters. In everyday life, the designation of values \u200b\u200bin the metric system began to be crowned with elements used in the United States. For example, computer discs, diagonals of monitors and other components are indicated in inches. At the same time, initially the parameters of these components were designated strictly in the values \u200b\u200bof the metric system (the width CD and DVD, for example, is 120 mm).

International use

Currently, the most common in the planet is a metric system of measures. The masses table, lengths, distances and other parameters makes it easy to translate some indicators to others. Countries, due to certain reasons not switched to this system, it remains less and less every year. Such states continuing to use their own parameters include the United States, Burma and Liberia. America enjoys in the sectors of the SI system. All others used American parameters. The United Kingdom and Saint Lucia have not yet moved to the world system of SI. But, I must say that the process is in the active stage. The last of the countries that finally switched to the metric system in 2005, Ireland became. Antigua and Guyana only produce a transition, but the pace is very slow. The situation in China, which officially moved to the metric system, but at the same time the use of the ancient Chinese units continues on its territory.

Aviation parameters

The metric system of measures is recognized almost everywhere. But there are separate industries in which she did not fit. In aviation, the measurement system is still used, which is based on such values \u200b\u200bas foot and mile. The use of this system in this area has developed historically. The position of the international organization of civil aviation is unequivocal - the transition to metric values \u200b\u200bshould be carried out. However, these recommendations in their pure form adhere to only several countries. Among them are Russia, China and Sweden. Moreover, the civil aviation structure of the Russian Federation, in order to avoid confusion with international dispatching points, in 2011 partially adopted a system of measures, the main unit of which ft.