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The experience of Ioffe and Milliken. I fulfilled the teacher of physics MKOU "Sosh with. Legostayevo "Provekina V.S. Dividability of an electric charge.
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The experience of Ioffe and Milliken to the beginning of the XX century. The existence of electrons was established in a number of independent experiments. But despite the huge experimental material accumulated by various scientific schoolsThe electron remained, strictly speaking, a hypothetical particle. The reason is that there was not a single experience in which solitary electrons would participate.
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Implex and Millique experience for answering this question in 1910-1911, American scientist Robert Andrews Milliken and Soviet physicist Abram Fedorovich Ioffe, independently of each other, made accurate experiments in which it was possible to monitor single electrons.
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The experience of Ioffe and Milliken in their experiments in the closed vessel 1, the air from which pumps the pump to a high vacuum, there were two horizontally arranged metal plates 2. Between them through the tube 3 placed cloud of charged metal dust or oil droplets. They were observed in a microscope 4 with a special scale, allowed to observe their sedimentation (fall) down. Suppose that dust or droplets to the room between the plates were charged negatively. Therefore, their settlement (drop) can be stopped if low plate Charge negatively, and upper - positively. And they did, seeking the equilibrium of the dust (droplets), followed by the microscope, then the charge of dusty (droplets) was reduced by acting on them ultraviolet or x-ray radiation. Dustkins (droplets) began to fall, as the supportive electrical force decreased.
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the experience of Ioffe and Millykein informing the metal plates an additional charge and this enhanced electric field, the dusty stopped again. So did several times, each time the special formula calculates the charge of the dust. The experiences of Millykein and Ioffe showed that drops of droplets and dusting always change jumps like. The minimum "portion" of an electric charge is an elementary electric charge equal to E \u003d 1.6 · 10-19 CL. However, the charge of the dusty goes not by itself, but with a particle of matter. Consequently, in nature there is such a particle of a substance that has the smallest charge, further indivisible - electron charge. Thanks to the experiments of Ioffe-Millique, the existence of an electron turned out of the hypothesis to a scientifically confirmed fact.
At the beginning of the XX century. The Soviet physicist Abram Fedorovich Ioffe and the American scientist Robert Millique (independently of each other) have experienced experiments that have proven the existence of particles that have the smallest electrical charge, and allowed to measure this charge.
What was the experience, you know from the textbook. We want to tell a little about the life and activities of these physicists and quote excerpts from their books, where they talk about their experiment.
Abram Fedorovich Ioffe was born in 1880 in Ukraine in Romny. He graduated from the St. Petersburg Institute of Technology in 1902 and left to Germany to continue education. He studied at the University of Munich, who graduated in 1905 by his teacher was the famous V. X-ray. In 1906, Ioffe returned to Russia with a diploma of the Philosophical Sciences of the University of Munich and began scientific and pedagogical activities at the St. Petersburg Polytechnic Institute. In 1915 he was assigned the degree of Dr. Petersburg University for the study of elastic and electrical properties quartz.
After October revolution According to his proposal, and under his leadership, a physician-technical department is organized in the newly created State Institute of X-ray and X-ray. The situation in which I had to work was difficult: went civil War; The young Soviet state was in the rings of enemies, which were supported by the capitalists of the whole world; hunger; devastation; Old scientific frames did not all accepted the revolution, part of the border went abroad; Scientific relations with other countries are almost completely interrupted. And at this time, A. F. Iofe, with the assistance of A. V. Lunacharsky, created a scientific institution in Petrograd, which became the hedge big number Research institutes of our country.
In 1921, the Physical and Technical Department of the State Institute of X-ray and X-ray media stated in an independent physico-technical institution, which A. F. Ioffe became the leader. And later, the Ukrainian Physico-Technical Institute, the Ural Physico-Technical Institute, the Institute of Chemical Physics and many others, were subsequently stood out of this institution and became independent scientific institutions.
Venidary scientists of our country I. V. Kurchatov, P. L. Kapitsa, N. N. Semenov, L. D. Landau, B. P. Konstantinov, I. K. Kikoin and many others started their scientific work Under the leadership of A. F. Ioffe, consider themselves his students and always with great warmth and love remembers him.
"Abram Fedorovich Ioffe from the first days of the revolution fell on the side of Soviet power, he became one of the prominent leaders of the front of physical education and science. The huge talent of the scientist, the teacher, the organizer, as well as a benevolent attitude towards people, personal charm, loyalty to public interests - all this determined the invaluable contribution of A. F. Ioffe to the development of Soviet physics. Many of my comrades are physicists, like me, - believe and call Academician Ioffe by the father of Soviet science, and this opinion, I believe, will be generally recognized in the history of Soviet science, "P. Konstantinov wrote academician.
The scientific activity of Ioffe was wide and diverse. He was an excellent experimental, engaged in issues of semiconductor physics, paid a lot of attention to the implementation of scientific research results, participated in the development of military equipment, in particular it was proposed by the principle of radar for the detection of enemy aircraft, and was interested in the possibility of using the achievements of science in agriculture.
The large scientific and organizational activities of A. F. Ioffe received wide recognition in the country. He was elected a full member of the USSR Academy of Sciences, he was awarded the title of Hero of Socialist Labor, the title of Honored Worker of Science of the USSR, he was awarded the first degree premium, was awarded two orders of Lenin. Many foreign academies and universities elected him with their honorable member.
Robert Milliekin was born in 1868 in Illinois in the priest's family. His childhood passed in the small town of Macvoket. In 1893 he entered the University of Columbia, then he studied in Germany.
At the age of 28, he was invited to teach the University of Chicago. Initially, he was engaged in almost extremely pedagogical work and only in forty years began scientific researchwho brought him world glory.
"One of the first in a number of brilliant experimenters, founding and substantiated new physics, should be called Robert Millykein ... Characteristic feature Research of Millykein is their completely exceptional accuracy. Millilen in many cases repeated the experiments invented and even fulfilled by other persons, but did them with such care and prudence, which its results became an indisputable and inevitable base of theoretical construction. Most Milliona Merit - Measurement of Electron Charge e.and the constant theory of quanta A, "the academician S. I. Vavilov wrote about this academician.
For their own experimental studies R. Milliekin in 1924 was awarded Nobel Prize.
Milliken died in 1953
How did you manage to measure the charge of a separate electron?
This is what they write about their experiments A. F. Ioffe and R. Milliken.
A. F. Ioffe: "... in the chamber BUTsmall zinc dusting were created, which were falling through a narrow hole into the space between two charged plates. Charged dust drops down, experiencing, like every body, gravity. But if it is charged, electric forces act on it depending on the charge sign in the bottom up or top down. Featuring the electric charge of the plates, it was possible to stop each falling particle so that it is motionless in the air. I managed to keep the whole day in such a state. When the bunch of ultraviolet light fell on it, he reduced the charge. It could immediately notice that with a change in charge, the electric force decreased, while the power of gravity did not change: the equilibrium was broken, the particle began to fall.
I had to select another charge of the plates to stop the zinc dust again. And every time we had the opportunity to measure her charge ...
It was possible to remove 1, 2, 3, 4, 5, 6, 1... up to 50 charges, but it was always an integer number of electrons. It turned out that whatever substance would be taken, be it zinc, oil, mercury, whether it will be the action of light, or heating, or other impact, - whenever the body loses the charge, it always loses with an electrical electron. So it was possible to conclude that only entire electrons exist in nature. "
R. Milliken: "... With the help of an ordinary sprayer to the chamber FROMthe jet of oil was allowed. The air, by means of which a jet was blunting, was released first from dust by passing through a tube with a glass cotton. The droplets of the oil, which made a stream, were very small; The radius of most of them was about 0.001 mm. These droplets fell slowly in the chamber with, sometimes some of them passed through a small hole rin the center of a round brass plate M.a diameter of 22 cm, composition-operating one of the plates of the air capacitor. Other plate - N.- accounted for 16 mm lower below with three ebonite racks but.These plates could charge (one positively, and the other negatively) with the help of the switch 5 connecting them with poles 10,000-volt rechargeable battery IN.Oil droplets that appear near r,illuminated by a strong bundle of light, passing through two windows located in an ebony ring one against the other. If you look through the third window ABOUT,directed to the reader, a drop seems to be a bright asterisk on a dark background. Drops passing through a hole r,turned out to be usually highly charged due to friction while blowing jet ...
Drops having charges of one sign with an upper plate, as well as having too weak charges of the opposite sign, quickly fall. The same drops that have too many charges of the opposite sign are rapidly attracted by the upper plate, overcoming gravity. As a result, after 7 or 8 minutes, the field of view is quite clarified, and it remains only a relatively small number of drops, namely those that have a charge, just sufficient to be supported by an electric field. These drops seem clearly visible bright dots. I received only one such asterisk several times in the whole field, and she kept there for about a minute ...
In all cases, without any exception, it turned out that both the initial charge arising from the friction and numerous charges captured by the drops of ions are equal to the exact multiple of the smallest charge trapped from the air. Some of these droplets did not have initially no charge, and then captured one, two, three, four, five, six or seven elementary charges or electrons. Other drops originally had seven or eight, sometimes twenty, sometimes fifty, sometimes a hundred, sometimes one hundred fifty elementary units and captured in each case one or more dozens of elementary charges in continuation of observations. Thus, drops were observed with all sorts of electrons between one and a hundred fifty ... when the number does not exceed the fifty, then the error is also impossible here, as with the score of their own fingers. However, when the electron counting is calculated in the charge, in which they are contained over a hundred or two hundred, it is impossible to be confident in the absence of an error ... but it is absolutely impossible to imagine to be big charges, like, for example, those with which we deal in the technical applications of electricity were built essentially otherwise than those small charges that we can count ...
Wherever the electric charge meets - on insulators or on conductors, in electrolytes or metals, - everywhere it has a sharply pronounced grainy structure. It consists of an integer number of units of electricity (electrons), which are all the same. In electrostatic phenomena, these electrons are scattered over the surface of the charged body, and in the electric current they move along the conductor. "
Details Category: Electricity and Magnetism Published 08.06.2015 05:51 Views: 5425One of the fundamental constants in physics is an elementary electric charge. This is a scalar value characterizing the ability physical tel Take part in electromagnetic interaction.
An elementary electrical charge is considered to be the smallest positive or negative charge that cannot be divided. Its value is equal to the charge of an electron.
The fact that any electric charge occurring in nature is always equal to an integer number of elementary charges, in 1752 he suggested a well-known politician Benjamin Franklin, politician and diplomat, who also studied scientific and inventive activities, the first American, who became a member of the Russian Academy of Sciences.
Benjamin Franklin
If the assumption of Franklin is true, and the electrical charge of any charged body or the bodies system consists of an integer number of elementary charges, then this charge may vary jump-like by a value containing an integer electron charges.
For the first time, it was possible to confirm and quite accurately determine the electron charge with an experienced by American scientist, Professor of the University of Chicago, Robert Milliken.
Millionale experience
Millykeine experience scheme
His first famous experience with Milliken oil droplets in 1909, along with his assistant Harvey Fletcher. It is said that at first the experience was planned to do with droplets of water, but they evaporated in a few seconds, which turned out clearly not enough to get the result. Then Millilen sent a flatchtop in a pharmacy, where he acquired a spray gun and an oil bubble for watches. This turned out to be enough to experience the experience. Subsequently, Milliekin received the Nobel Prize for him, and Flacher Doctor's degree.
Robert Millique
Harvey Fletcher
What was the experiment of Millykein?
The electrified oil droplet under the influence of gravity falls down between two metal plates. But if you create an electric field between them, it will keep the drop from falling. Measuring the power of the electric field, you can determine the charge of the drop.
Two metal condenser plates Experimentators are located inside the vessel. The smallest droplets of oil were introduced there with the help of a sprayer, which charged negatively during splashing as a result of their friction about the air.
In the absence of electric field, the droplet drops
Under the action of gravity f w \u003d mg, the droplets began to fall down. But so they were not in a vacuum, but in the medium, then freely falling to them prevented the power of air resistance F res \u003d 6πη rV 0. where η - Air viscosity. When F W. and F Res. balanced, the drop becomes uniform at speed v 0 . Measuring this speed, the scientist determined the radius of the drop.
Droplet "PARIT" under the action of an electric field
If at the time of falling the droplet on the plates was supplied voltage in such a way that the upper plate was positive charge, and the lower negative, the fall was discontinued. He prevented the resulting electric field. The droplets seemed to hang. It happened when the power F R. balanced by force acting from the electric field F R \u003d. eE ,
where F R - the resulting gravity and the forces of Archimedes.
F R \u003d 4/3 · πr 3 ( ρ – ρ 0) g.
ρ - density of oil droplets;
ρ 0 – air density.
r. - Radius drops.
Knowing F R. and E. , you can define the value e. .
Since it was very difficult to achieve a droplet for a long time in a fixed state, it was very difficult, then Millikin and Fletcher created such a field in which the droplet after the stop began to move up at a very low speed v. . In this case
Experiments repeated many times. Charges were reported to droplets, irradiating them X-ray or ultraviolet installation. But every time the total charge of the drop has always been equal to several elementary charges.
In 1911, Milliekin found that the electron charge value is 1.5924 (17) x 10 -19 CL. The scientist was mistaken by 1%. The current value is 1,602176487 (10) x 10 -19 CL.
Experience Ioffe
Abram Fedorovich Ioffe
It must be said that almost simultaneously with a milliken, but regardless of him, such experiments conducted a Russian physicist Abram Fedorovich Ioffe. And his experimental installation was similar to installing Millique. But the air was pumped out of the vessel, and there was a vacuum in it. And instead of the oil droplets, Ioffe used small charged zinc particles. Behind their movement was observed in a microscope.
Installing Ioffe
1- a tube
2- camera
3 - metal plates
4 - microscope
5 - ultraviolet emitter
Under the electrostatic field, the dusting zinc made a fall. As soon as the force of gravity of the dusty became equal to the force acting on her from the side of the electric field, the fall stopped. While the charge of the dusty did not change, she continued to hang motionless. But if it was affected by ultraviolet light, then it was charged, and the equilibrium was broken. She began to fall again. Then they increased the charge value on the plates. Accordingly, the electric field increased, and the fall stopped again. So did several times. As a result, it was found out that each time the dust charge was changed by the magnitude, the multiple size of the elementary particle charge.
The magnitude of the charge of this particle Ioffe did not calculate. But, by conducting such an experience in 1925 together with the physicist N.I. Dobronravov, somewhat modifying an experienced installation and using the dust bismuth instead of Zinc, he confirmed the theory
Presentation on the topic: Physicians. F. Ioffe and R. E. Milliken. Their life path. Ioffe experience - Milliken
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Presentation on the topic: Physicians. F. Ioffe and R. E. Milliken. Their life path. Ioffe experience - Milliken
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The experience of Joffe - Milliken by the end of the nineteenth century in a number of a wide variety of experiments it was found that there is some carrier negative chargewhich was called the electron. However, it was actually a hypothetical unit because, despite the abundance practical materialNo experiment was conducted with the participation of a single electron. It was not known whether there are varieties of electrons for different substances or it is always the same, which charge is carrying an electron, whether the charge exists separately from the particle. In general, in the scientific environment about an electron there were hot spores, and a sufficient practical base that would definitely stopped all debates, was not.
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The figure shows the installation scheme used in the experiment A. F. Ioffe. In the closed vessel, the air of which is dumped to a high vacuum, there were two metal plates P, located horizontally. From the chamber and through the hole about the space between the plates, the minor charged zinc dusts fell. These dusty observed in a microscope. The figure shows the installation scheme used in the experiment A. F. Ioffe. In the closed vessel, the air of which is dumped to a high vacuum, there were two metal plates P, located horizontally. From the chamber and through the hole about the space between the plates, the minor charged zinc dusts fell. These dusty observed in a microscope.
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So, charged dust and droplets in vacuum will fall from the top plate on the bottom, however, this process can be stopped if you charge the top plate positively, and the lower negative. So, charged dust and droplets in vacuum will fall from the top plate on the bottom, however, this process can be stopped if you charge the top plate positively, and the lower negative. The resulting electric field will act the Coulomb forces on charged particles, preventing them from falling. Adjusting the value of the charge, sought the fact that the dusting batted in the middle between the plates. Next, reduced the charge of dust or drops, irradiating them with an x-ray or ultraviolet. Losing charge, dust started to fall again, they were again stopped, adjusting the charge of the plates. Such a process was repeated several times, calculating the charge of droplets and dust in special formulas. As a result of these studies, it was possible to establish that the charge of dust or drops always changed with jumps, on a strictly defined value, or on the size, multiple is the value.
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Abram Fedorovich Ioffe Abram Fedorovich Ioffe - a Russian physicist who made many fundamental discoveries and spent a huge amount of research, including in the field of electronics. He conducted studies of the properties of semiconductor materials, opened the rectifting property of the transition of the metal-dielectric, subsequently explained using the theory of the tunnel effect, suggested the possibility of transforming light in electricity.
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Abram Fedorovich was born on October 14, 1980 in the city of Romny Poltava province (now Poltava region, Ukraine) in the family family. Since the father of Abraha was a rich man quite rich, he did not dreamed to give a good education His son. In 1897, Ioffe gets secondary education in the real school native city. In 1902, he ends with the St. Petersburg Technological Institute and enters the University of Munich in Germany. In Munich, he works under the leadership of Wilhelm himself Konrad X-ray. Wilhelm Konrad, seeing the scenery and not ababa what talent of the student is trying to persuade Abram to stay in Munich and continue scientific activities, but Ioffe turned out to be a patriot of his country. After graduating from the University in 1906, having received a scientific degree of Doctor of Philosophy, he returns to Russia. Abram Fedorovich was born on October 14, 1980 in the city of Romny Poltava province (now Poltava region, Ukraine) in the family family. Since the father of Abraha was a rich man quite rich, he did not dreamed to give a good formation to his son. In 1897, Ioffe gets secondary education in the real school of his hometown. In 1902, he ends with the St. Petersburg Technological Institute and enters the University of Munich in Germany. In Munich, he works under the leadership of Wilhelm himself Konrad X-ray. Wilhelm Konrad, seeing the scenery and not ababa what talent of the student is trying to persuade Abram to stay in Munich and continue scientific activities, but Ioffe turned out to be a patriot of his country. After graduating from the University in 1906, having received a scientific degree of Doctor of Philosophy, he returns to Russia.
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In Russia, Ioffe is arranged for a robot in the Polytechnic Institute. In 1911, he experimentally determines the value of the charge of an electron on the same method as Robert Milline (in the electrical and gravitational fields, metal particles were bated). Due to the fact that Ioffe published his work only two years later - the fame of the opening of the elevation of the charge of an electron went to American physics. In addition to determining the charge, Ioffe proved the reality of the existence of electrons, regardless of matter, investigated the magnetic effect of the electron flow, proved the static character of electron departure with an external photo effect. In Russia, Ioffe is arranged for a robot in the Polytechnic Institute. In 1911, he experimentally determines the value of the charge of an electron on the same method as Robert Milline (in the electrical and gravitational fields, metal particles were bated). Due to the fact that Ioffe published his work only two years later - the fame of the opening of the elevation of the charge of an electron went to American physics. In addition to determining the charge, Ioffe proved the reality of the existence of electrons, regardless of matter, investigated the magnetic effect of the electron flow, proved the static character of electron departure with an external photo effect.
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In 1913, Abram Fedorovich defends Master, and two years later his doctoral dissertation in physics, which was the study of the elastic and electrical properties of quartz. In the period from 1916 to 1923, he actively studies the mechanism electrical conductivity different crystals. In 1923 it was on the initiative of Ioffe begins fundamental research and studying properties, completely new ones at the time of materials - semiconductors. The first work in this area was carried out with the direct participation of Russian physics and concerned the analysis of electrical phenomena between the semiconductor and the metal. They found a straightening property of a metal-semiconductor transition, which only 40 years later was justified using the theory of the tunnel effect. In 1913, Abram Fedorovich defends Master, and two years later his doctoral dissertation in physics, which was the study of the elastic and electrical properties of quartz. In the period from 1916 to 1923, it actively studies the mechanism of electrical conductivity of various crystals. In 1923, it was on the initiative of Imoffs that fundamental studies begin and studying properties, completely new ones at the time of materials - semiconductors. The first work in this area was carried out with the direct participation of Russian physics and concerned the analysis of electrical phenomena between the semiconductor and the metal. They found a straightening property of a metal-semiconductor transition, which only 40 years later was justified using the theory of the tunnel effect.
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Exploring the photo effect in semiconductors, Ioffe expressed quite bold at that time the idea that this method can be converted to the energy of light into electric current. This has become a prerequisite in the future to create photoelectric generators, and in particular silicon converters, in the consequence of used as part solar batteries. Together with their students, Abram Fedorovich creates a semiconductor classification system, as well as the method of determining their main electrical and physical properties. In particular, the study of their thermoelectric properties, in consequence it became the basis for the creation of semiconductor thermoelectric refrigerators, widely used throughout the world in areas of electronics, instrument making and cosmic biology. Exploring the photo effect in semiconductors, Ioffe expressed quite bold at that time the idea that this method can be converted to the energy of light into electric current. This was the prerequisite in the future to create photoelectric generators, and in particular silicon converters, in the consequence of used as part of solar cells. Together with his students, Abram Fedorovich creates a semiconductor classification system, as well as a methodology for determining their main electrical and physical properties. In particular, the study of their thermoelectric properties, in consequence it became the basis for the creation of semiconductor thermoelectric refrigerators, widely used throughout the world in areas of electronics, instrument making and cosmic biology.
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Abram Fedorovich Ioffe made a huge contribution to the formation and development of physics and electronics. He was a member of many academies of sciences (Berlin and Gottenna, American, Italian), as well as honorary member of many universities around the world. For their achievements and research, a variety of awards was awarded. Died Abram Fedorovich on October 14, 1960. Abram Fedorovich Ioffe made a huge contribution to the formation and development of physics and electronics. He was a member of many academies of sciences (Berlin and Gottenna, American, Italian), as well as honorary member of many universities around the world. For their achievements and research, a variety of awards was awarded. Died Abram Fedorovich on October 14, 1960.
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Millilen Robert Endrus American Physicist Robert Millique was born in Morrison (Illinois) on March 22, 1868 in the family of a priest. After graduation high School Robert enters the Obourlin College in Ohio. His interests were focused on mathematics and ancient Greek. For the sake of earnings, he has exposed physics in college for two years. 1891 Millilen received a bachelor's degree, and 1893 - a master's degree in physics.
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In Columbia University, Milliken studied under the guidance of famous physics M.I.Pupina. He spent one summer at the University of Chicago, where he worked under the leadership of the famous physicist-experimental Albert Abraham Maykelson. In Columbia University, Milliken studied under the guidance of famous physics M.I.Pupina. He spent one summer at the University of Chicago, where he worked under the leadership of the famous physicist-experimental Albert Abraham Maykelson.
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1896 Millilen returned to the University of Chicago, where he became an assistant Michelson. 1896 Millilen returned to the University of Chicago, where he became an assistant Michelson. For further twelve years, Milliekin wrote several physics textbooks, which were adopted as textbooks for colleges and secondary schools (with additions remained over 50 years). In 1910, MilliKena was appointed professor of physics.
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Robert Millique has developed a droplet method that has given the opportunity to measure the charge of individual electrons and protons (1910 - 1914) a large number of experiments on accurate electron charge calculation. Thus, he experimentally proved the discreteness of the electric charge and for the first time quite accurately determined its value (4.774 * 10 ^ -10 electrostatic units). I checked the Einstein equation for a photoelectric effect in the field of visible and ultraviolet rays, defined a constant plank (1914). Robert Milliekin has developed a droplet method, which has given the opportunity to measure the charge of individual electrons and protons (1910 - 1914) a large number of experiments on accurate electron charge calculation. Thus, he experimentally proved the discreteness of the electric charge and for the first time quite accurately determined its value (4.774 * 10 ^ -10 electrostatic units). I checked the Einstein equation for a photoelectric effect in the field of visible and ultraviolet rays, defined a constant plank (1914).
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1921 Millilen was appointed director of the new Bridgechivsky Physical Laboratory and Head of the California Executive Committee technological Institute. 1921 Millilen was appointed director of the new Bridgechi physical laboratory and head of the executive committee of the California Institute of Technology. Here, he completed a large cycle of cosmic rays, in particular experiments (1921 - 1922) with air shutters with self-compound electroscopes at altitudes 15500 m. 1923, MilliKen was awarded the Nobel Prize in the field of physics "For work on the definition of elementary electric charge and photoelectric effect "
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During 1925-1927. Millilen demonstrated that ionizing action Space radiation decreases with depth, and confirmed the extraterrestrial origin of these "cosmic rays". Exploring the trajectories of cosmic particles, revealed alpha particles, quick electrons, protons, neutrons, positrons and gamma quanta. Regardless of Vernova, the latitudinal effect of cosmic rays in the stratosphere was opened. During 1925-1927. Milline has demonstrated that the ionizing effect of cosmic radiation decreases with depth, and confirmed the extraterrestrial origin of these "cosmic rays". Exploring the trajectories of cosmic particles, revealed alpha particles, quick electrons, protons, neutrons, positrons and gamma quanta. Regardless of Vernova, the latitudinal effect of cosmic rays in the stratosphere was opened.
\u003e Millique experience
What is Millionale experience - Experiment with oil drop. Read detailed description Experience and conclusions, equations, electron charge, limit speed.
In 1911, with the help of charged oil droplets, Robert Millique was able to form an electron charge.
Task learning
- To understand the difference between the real charge of the electron and created by the milliona.
Major points
- The experiment participated ionizing oil drops. Finding into the air, they balance the strength of gravity with the power of the electric field.
- Millilen could not directly calculate the number of electrons in each oil drop, but revealed a common denominator - 1.5924 (17) x 10 -19 s (electron charge).
- The resulting value is different from the 1% adopted - 1.602176487 (40) x 10 -19 C.
Terms
- The electric field is a plot around the charged particle or between two voltages.
- Voltage is the amount of electrostatic potential between two points in space.
- The limit speed is the speed with which the object in frequent fall stops acceleration down, because the strength of gravity is equal and opposite to the resistance.
Experiment with oil drop
This is one of the most meaningful research in the history of physical science. For his implementation, Robert Millilen and Harvey Fletcher began in 1911. They wanted to determine the charge of one electron.
For this, Milliekin used a sprayer to create a fog of tiny oil droplets in the chamber where there was a hole. Some drops failed in the hole and the camera, where scientists figured out the final speed and mass
Next, the Milline has exposed drops to X-rays, ionizing molecules in the air and forcing the electrons to attach to oil drops. This led to charging. The top and bottom of the chambers were connected to the battery, and the potential difference represented the electric field.
Milline was able to balance the gravity and strength of the electric field, which is why oil drops were exposed to the air.
The device has a parallel pair of horizontal metal plates. In the space between them a uniform electric field is formed. The ring possesses three holes for the suspension and one to observe the microscope. Special oil is sprayed into the chamber, where the drops are electrically charged. Drops enter the space between the plates and can be controlled through a change in voltage on the plates
It had a mass of oil droplets and acceleration of gravity (9.81 m / s 2), as well as X-ray energy, due to which the charge calculated.
The charge of each drop remained a mystery, so Millicine adjusted the force of X-rays, ionizing air, and also calculated the remaining values. In each case, the charge reached 1.5924 (17) x 10 -19 C. The results were very accurate and differed in only 1% of what is used now - 1.602176487 (40) x 10 -19 C.
This experiment was extremely important to determine the charge of an electron and evidence of the existence of particles, less atom.
