Discovery of the electron: Joseph John Thomson

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Discovery of the electron: Joseph John Thomson
Discovery of the electron: Joseph John Thomson

In 1897, the British physicist Joseph John Thomson (1856-1940) discovered the electron after a series of experiments aimed at studying the nature of an electric discharge in a vacuum. The famous scientist interpreted the beam deflections of electrically charged plates and magnets as evidence that electrons are much smaller than atoms.

electron discovery

The great physicist and scientist should have become an engineer

Thomson Joseph John, a great scientist, physicist and mentor, was to become an engineer, as his father thought, but at that time the family did not have the means to pay for education. Instead, the young Thomson attended college at Macester and later at Cambridge. In 1884 he was appointed to the prestigious post of Professor of Experimental Physics at Cambridge, although he personally did very little experimental work. He discovered his talent for developing hardware and diagnosing related problems. Thomson Joseph John was a good teacher, inspiring his students and givingconsiderable attention to the broad problem of developing the science of teaching at the university and high school.

thomson joseph john

Nobel Laureate

Thomson received many different awards, including the Nobel Prize in Physics in 1906. He also had great pleasure in seeing some of his associates receive their Nobel Prizes, including Rutherford in chemistry in 1908. A number of scientists such as William Prout and Norman Lockyer have suggested that atoms are not the smallest particles in the universe and that they are built from more fundamental units.

thomson experience

Discovery of the electron (briefly)

In 1897, Thompson proposed that one of the basic units is 1,000 times smaller than an atom, this subatomic particle became known as the electron. The scientist discovered this through his research on the properties of cathode rays. He estimated the mass of the cathode rays by measuring the heat generated when the thermal transition rays hit and compared it to the magnetic deflection of the beam. His experiments show not only that cathode rays are 1000 times lighter than a hydrogen atom, but also that their mass was the same regardless of the type of atom. The scientist came to the conclusion that the rays are composed of very light, negatively charged particles, which are the universal building material for atoms. He called these particles "corpuscles", but later scientists preferred the name "electrons", proposed by George Johnston Stoney in 1891.

year of discovery of the electron

Thompson's experiments

Comparing the deflection of cathode beams with electric and magnetic fields, the physicist obtained more reliable measurements of the electron's charge and mass. Thomson's experiment was carried out inside special cathode ray tubes. In 1904, he hypothesized that the model of the atom is a sphere of positive matter in which the position of particles is determined by electrostatic forces. To explain the generally neutral charge of the atom, Thompson suggested that the corpuscles were distributed in a uniform field of positive charge. The discovery of the electron made it possible to believe that the atom could be divided into even smaller parts, and was the first step towards creating a detailed model of the atom.

history of the discovery of the electron

Discovery history

Joseph John Thomson is widely known as the discoverer of the electron. For most of his career, the professor has worked on various aspects of the conduction of electricity through gases. In 1897 (the year of the discovery of the electron), he experimentally proved that the so-called cathode rays are actually negatively charged particles in motion.

Many interesting questions are related directly to the opening process. Obviously, the characterization of cathode rays predated Thomson, and several scientists have already made important contributions. Can we then say with certainty that it was Thomson who was the first to discover the electron? After all, he did not invent the vacuum tube or the presence of cathode rays. The discovery of the electron is a purely cumulative process. Credited pioneer contributes the most importantcontribution, summarizing and systematizing all the experience accumulated before him.

the discovery of the electron briefly

Thomson cathode ray tubes

The great discovery of the electron was made with special equipment and under certain conditions. Thomson conducted a series of experiments using an elaborate cathode ray tube, which includes two plates, beams were supposed to travel between them. The long-standing controversy regarding the nature of cathode rays, which arise when an electric current passes through a vessel from which most of the air has been evacuated, has been suspended.

electron discovery

This vessel was a cathode ray tube. Using an improved vacuum method, Thomson was able to make a convincing argument that these beams were composed of particles, regardless of the type of gas and the type of metal that was used as a conductor. Thomson can rightfully be called the man who split the atom.

electron discovery

Scientific recluse? This is not about Thomson

The outstanding physicist of his time was by no means a scientific recluse, as one often thinks of brilliant scientists. He was the administrative head of the very successful Cavendish Laboratory. It was there that the scientist met Rose Elizabeth Paget, whom he married in 1890.

Thomson not only managed a number of research projects, he also funded the renovation of laboratory facilities with little support from the university and colleges. It was talentedteacher. The people he gathered around him from 1895 to 1914 came from all over the world. Some of them won seven Nobel Prizes under him.

electron discovery

It was while working with Thomson at the Cavendish Laboratory in 1910 that Ernest Rutherford conducted research that led to modern understanding of the internal structure of the atom.

Thomson took his teaching very seriously: he regularly lectured in elementary grades in the morning and taught science to graduate students in the afternoon. The scientist considered the doctrine useful for the researcher, since it requires periodically revising the basic ideas and at the same time leaving room for the possibility of discovering something new that no one had paid attention to before. The history of the discovery of the electron clearly confirms this. Thompson devoted most of his scientific activity to the study of the passage of electrically charged current particles through rarefied gases and vacuum space. He was engaged in the study of cathode and X-rays and made a huge contribution to the study of atomic physics. In addition, Thomson also developed a theory of electron motion in magnetic and electric fields.

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