UNIT 12

 

I. Find out the words in the dictionary. Write them down and learn.

 

influential, widely accepted, distinguished, a researcher, to probe, to emerge, bundles of energy, to conclude, speculation, certainty, probabilities, stable, a quantum jump, to urge, exchange, to encourage, to earn the respect

 

II. Read the text. Use a dictionary, if necessary.

 

Text: “Niels Bohr and Quantum Mechanics”.

 

Niels Bohr (1885-1962), a Danish physicist, was one of the greatest and most influential scientists of the twentieth century. Bohr developed basic ideas about the structure of an atom. These ideas have been widely accepted by scientists ever since. For his important work, Bohr was awarded the Nobel Prize in physics in 1922.

Bohr, along with other distinguished physicists of the early 1900’s, developed a new branch of physics known as quantum mechanics. These physicists recognized that the laws of motion and gravity formulated by Sir Isaac Newton in the 1600’s (called the Newtonian laws) could not properly explain motion at the atomic level. Newton had developed his physics with the movements of planets in mind. Early atomic researchers – scientists such as Ernest Rutherford and J.J.Thomson – had thought of atoms as tiny models of the solar system. As physicists probed deeper into the atom, however, they gradually realized that the solar system was not an accurate model for atomic motion.

Albert Einstein, Max Planck, Niels Bohr, and others developed the theories of quantum mechanics in the early 1900’s to better describe the atom and its motion. Several important ideas emerged. One idea is that radiation – such as light – is emitted in a stream of separate bundles of energy called quanta. This principle can also be applied to atomic radiation, such as that of electrons. These speculations led physicists to conclude that atomic particles, such as electrons, have properties of both particles and waves. This idea came to be known as the “wave-particle duality” principle. It revolutionized physics. No longer could scientists calculate with certainty the position of an electron in its orbit at a particular moment. Such movements, according to quantum mechanics, can be mathematically described only as probabilities. In other words, since a particle, such as an electron, has qualities of both a particle and a wave, the traditional Newtonian laws of bodies in motion do not apply to it.

Niels Bohr developed these ideas further. He claimed that an atom exists in a series of stable states. Between such states, a jump in energy level – a “quantumjump” – occurs in the atom. The jump can be to a higher energy level (increase) or to a lower energy level (decrease). Such a change in energy happens in a fraction of time. With every quantum jump, light photons are given off. Photons are quanta – tiny bundles – of light energy. Bohr based this theory on observations of thespectrum of light that the element hydrogen gives off. Every chemical element gives off a unique spectrum – that is, band of light frequencies. Bohr thought that the band of light frequencies given off by a chemical element could only be explained by the theory of “quantum jumps” of energy in the atom. Scientific observations made during and after his lifetime have proved his theory true.

Niels Bohr strongly influenced the physicists and scientists of his time. The reasons for this influence went beyond Bohr’s own contributions to physics. In 1921 the University of Copenhagen opened a new Institute of Theoretic Physics with Niels Bohr as its director. This institute became the world center for exchange of ideas among physicists. The institute owed much of its success and influence to its director. Bohr was a scientist who welcomed the exchange of ideas. He also formed close friendships with his co-workers and encouraged them in their work. In his own country as well as abroad, Niels Bohr earned the respect of fellow scientists. He served as president of the RoyalDanishAcademy from 1939 until his death in 1962.

 

III. Find an adverb in each line and translate it. Translate also the underlined words.

 

a) Conclude, motion, traditionally, unique, encourage.

b) Probability, unstable, conclude, gradually, fraction.

c) Exchange, abroad, observation, tiny, occur.

d) Certainty, widely, inaccurate, frequency, prove.

e) Influential, co-worker, chemical, properly, distinguish.

f) Strongly, subatomic, apply, success, urge.

 

IV. Practice the following speech patterns.

 

Pattern 1.  Bohr developed basic ideas about the structure of an atom.

 

1. Newton – the motion of bodies.

2. Einstein – space-time continuum.

3. Max Planck – the atom and its motion.

4. Ernest Rutherford – radioactivity.

5. James Clerk Maxwell – electromagnetism.

6. Galileo – the solar system.

7. Michael Faraday – electrical induction.

 

Pattern 2.  Bohr claimed that an atom exists in a series of stable states.

 

1. Ernest Rutherford – atoms can disintegrate.

2. J. J. Thomson – electrons are a fundamental part of all matter.

3. Max Planck – radiant energy is a stream of quanta of energy.

 

Pattern 3.  Bohr based this theory on observations of the spectrum of light.

 

1. Newton – movements of planets.

2. Joseph J. Thomson – cathode rays.

3. Michael Faraday – the electric current. 

 

V. Find the sentences that can’t be found in the text.

 

1. Bohr developed basic ideas about the structure of an atom.
2. Bohr’s work contributed strongly to most of the important discoveries in physics during and since his lifetime.
3. Bohr, along with other distinguished physicists of the early 1900’s, developed a new branch of physics known as quantum mechanics.
4. Albert Einstein, Max Planck, Niels Bohr, and other developed the theories of quantum mechanics in the early 1900’s to better describe the atom and its motion.
5. He claimed that an atom exists in a series of stable states.
6. Bohr based this theory on observations of the spectrum of light that the element hydrogen gives off.
7. Bohr thought that the band of light frequencies given off by a chemical element could only be explained by the theory of “quantum jumps” of energy in the atom. 

 

VI. Find English equivalents to the following words and expressions in the text.

 

1. один из самых влиятельных учёных ___________________________
2. не могли объяснить должным образом _________________________
3. модели солнечной системы ___________________________________
4. чтобы лучше объяснить атом и его движение ____________________
5. идеи возникли ______________________________________________
6. этот принцип можно применить _______________________________
7. принцип корпускулярно-волнового дуализма ___________________
8. совершил революцию в физике _______________________________
9. устойчивые состояния _______________________________________
10. более высокий энергетический уровень ________________________
11. излучаются фотоны света ____________________________________
12. свой собственный спектр _____________________________________
13. значительно повлиял на ученых своего времени _________________
14. вклад в физику _____________________________________________

 

VII. Find Russian equivalents to the following words and expressions in the text.

 

1. the ideas have been widely accepted _________________________________
2. along with other distinguished physicists _____________________________
3. with the movements of planets in mind _______________________________
4. probed deeper into the atom _______________________________________
5. an accurate model for atomic motion ________________________________
6. a stream of bundles of energy ______________________________________
7. probabilities ____________________________________________________
8. a quantum jump _________________________________________________
9. happens in a fraction of time _______________________________________
10. band of light frequencies __________________________________________
11. welcomed the exchange of ideas ____________________________________
12. earned the respect ________________________________________________

 

VIII. Analyze the structure of the following sentences.

 

1. These speculations led physicists to conclude that atomic particles, such as electrons, have properties of both particles and waves.
2. No longer could scientists calculate with certainly the position of an electron in its orbit at a particular moment.
3. Bohr thought that the band of light frequencies given off by a chemical element could only be explained by the theory of “quantum jumps” of energy in the atom.
4. Scientific observations made during and after his lifetime have proved his theory true.

 

IX. Fill in the missing words.

 

1. Niels Bohr was one of the greatest and most ______ scientists of the twentieth century.
2. For his important work, Bohr was ______ the Nobel Prize in _______ in 1922.
3. Bohr developed a new branch of physics known as ________ mechanics.
4. As physicists _______ deeper into the atom, however, they gradually realized that the solar system is not an ________ model for atomic motion.
5. One idea is that radiation – such as light – is emitted in a stream of separate ________ of energy called quanta.
6. This idea came to be known as the “_______ _______ duality” principle.
7. Such movements, according to quantum mechanics, can be mathematically described only as _________.
8. Niels Bohr ________ these ideas further.
9. Between such states, a ________ in energy level ________ in the atom.
10. With every quantum jump, light photons are ________ ________.

 

X. Fill in the prepositions if necessary.

 

1. Bohr developed basic ideas ___ the structure ___ an atom.
2. ___ his important work, Bohr was awarded the Nobel Prize ___ physics ___ 1922.
3. The laws ___ motion and gravity formulated ___ Newton ___ the 1600’s could not explain motion ___ the atomic level.
4. Newton had developed his physics ___ the movements ___ planets ___ mind.
5. No longer could scientists calculate ___ certainly the position ___ an electron ___ its orbit ___ a particular moment.
6. The jump can be ___ a higher energy level or ___ a lower energy level.
7. ___ every quantum jump, light photons are given ___.
8. Bohr based this theory ___ observations ___ the spectrum ___ light that the element hydrogen gives ___.
9. The reason ___ this influence went ___ Bohr’s own contribution ___ physics.
10. The institute owned much ___ its success and influence ___ its director.

 

XI. Practice with someone asking and answering.

 

1. What was Niels Bohr?
2. What ideas did Bohr develop?
3. Was Bohr awarded any prize for his work?
4. What branch of physics did Bohr develop?
5. Why couldn’t the laws of motion and gravity formulated by Sir Isaac Newton properly explain motion at the atomic level?
6. When did physicists realize that the solar system was not an accurate model for atomic motion?
7. Why did Albert Einstein, Max Planck, Niels Bohr and others develop the theories of quantum mechanics?
8. What important principle was formulated in connection with the theories of quantum mechanics?
9. How can the movements of an electron in its orbit be mathematically described?
10. What did Niels Bohr claim?
11. What did Bohr base his theory on?
12. Why did he earn the respect of fellow scientists?

 

XII. Translating in Russian without using a dictionary.

 

Bohr appreciated friendly disagreements in science. Niels Bohr was born in Copenhagen, Denmark, in 1885. His father was a famous professor at the University of Copenhagen. His mother was from a family that had been important in banking and in government. The Bohr children were encouraged to excel in their studies. Niels’s brother, Harald, became a brilliant mathematician.

Niels attended the University of Copenhagen, where he won a gold medal from the RoyalDanishAcademy of Sciences and Letters for original scientific research. In 1911 he went to England to study with the great physicist Sir J.J.Thomson at CambridgeUniversity. The next year he went to the University of Manchester, where he studied with Ernest Rutherford. At this time, Rutherford was developing his nuclear model of the atom. Rutherford’s ideas profoundly affected Bohr and led to the younger man’s own landmark theories. In 1912 Bohr returned to Copenhagen. Eventually he became a professor at the University of Copenhagen and director of the Institute of Theoretical Physics.

During the 1920’s and 1930’s, Bohr exchanged ideas with most of the physicists of the time and travelled widely. This creative and satisfying period came to an abrupt end in 1940 when Nazi Germany invaded and occupied Denmark. Bohr and his family escaped to Sweden in a fishing boat. Later Bohr and his son went to England, where they worked on projects to develop a nuclear fission bomb. This research eventually led Bohrs, father and son, to the Los Alamos, New Mexico, laboratory that made the first practical atomic bomb in 1945.

Meanwhile, Bohr had become deeply worried about the dangers of the atomic weapon upon which he was working. He talked to both President Roosevelt and Prime Minister Churchill about the need for international atomic cooperation.

Bohr also promoted such postwar international efforts as the First International Conference on the Peaceful Uses of Atomic Energy (Geneva, Switzerland, 1955). He also helped create the European Council for Nuclear Research (CERN). For these efforts, Niels Bohr received the first U.S. Atoms for Peace Award in 1957. When Bohr died in 1962 he was widely recognized as one of the greatest scientists, public figures, and peace advocates of his time.

 

XIII. Dictation – translation.

 

1. Нильс Бор – один из самых влиятельных учёных ХХ века.
2. Бор разработал основные идеи относительно структуры атома.
3. Бор вместе с другими выдающимися учёными начала XX века разработал новую область физики, известную как квантовая механика.
4. Эти учёные утверждали, что законы движения и гравитации, сформулированные Ньютоном, не могли полностью объяснить движение на атомном уровне.
5. По мере того, как физики в своих исследованиях погружались глубже внутрь атома, они постепенно убеждались, что солнечная система не является точной моделью для движения на уровне атома.
6. Эти размышления привели физиков к выводу, что частицы атома, такие как электроны, обладают свойствами как частицы, так и волны.
7. Учёные больше не могли определить с точностью положение электрона на орбите в определённый момент.
8. Так как частица, такая как электрон, обладает свойствами как частицы, так и волны, традиционные законы движения Ньютона не применимы к ней.
9. При каждом квантовом скачке излучаются фотоны света.
10. Бор строил свою теорию на наблюдениях за спектром света, который излучает такой элемент, как водород.