Чучкина Инноватион течнологиес 2011

•The company's winning formula includes excellent service and quality products.

5. Practise the pronunciation of the following words from Reading 7A .

Occurrence [ə'kΛrəns], occur [ə'kə:], feature ['fi:t∫ə], gravitational ['grævi'tei∫ənl], exert [ig'zə:t], engineering ['end3i'niəriŋ], content ['kontent], macroscopic ['mækrou 'skopik], physics ['fiziks], physicist ['fizisist], though [' ðou ], concept [' konsept], ultimate ['Λltimit], systematize ['sistimətaiz], systematization ['sistiməti'zei∫n], constituent[kən'stitjuənt], nuclei ['nju:kliai], electron [i'lektrən], proton ['proutən], neutron['nju:trən], neutrino [nju'tri:nou], quark [kwa:k], lepton ['lepton], cousin ['kΛzən], electromagnetism [i'lektrou'mægnitizm], quantitative ['kwontitətiv], quantity ['kwontiti], propagate ['propəgeit], diminish [di'mini∫ ], square ['skwεə], constant ['konstənt], proportionality [prə,po:∫ə'næləti], permeate ['pə:mieit], successfully [sΛk'sesfuli], applied [ə'plaid], celestial [si'lestjəl], mechanics [mi'kæniks], precise [pri'saiz], discrepancy [dis'krepnsi], acceleration [ək'selə'rei∫n],], equation [i'kwei∫n], obvious ['obviəs], distinguish [dis'tiŋgwi∫], inertial [i'nə:∫iəl], experiment [iks'perimənt], substitute ['sΛbstitju:t], principle ['principl], equivalence [i'kwivələns].

III.Reading 7A

FORCES

1.Before reading the text answer the following questions:

How many basic forces do you know? What basic forces do you know?

Upon reading the text check your answers.

One of the basic features in physics is the occurrence of forces that keep matter together. There are for example, the forces that keep the cells together to build up the human body, and there is the gravitational force that keeps us on the ground and the moon in orbit around the earth. We can ourselves exert forces when we push something and, by engineering, get some of the energy content in oil to produce force on the wheels of a car to move it. From the macroscopic point of view we can imagine many different kinds of forces, forces that act at impact but

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also forces that act over a distance such as the gravitational one. In physics, though, we try to systematise and to find as many general concepts as possible. One such systematisation lies in finding out the ultimate constituents of matter. Another is in finding out the forces that act between them. In the first case, we have been able to divide up matter into atoms and the atoms into nuclei and electrons, and then the nuclei into protons and neutrons. By colliding protons with protons or protons with electrons, particle physicists have uncovered that all matter can be built from a number of quarks (a concept introduced by Murray GellMann in the 60s) and leptons (electrons and neutrinos and their heavier cousins). In the same process physicists have uncovered four basic forces that act between these matter particles – gravitation, electromagnetism, the strong and the weak nuclear force. Only the first two, can be directly seen in the macroscopic world so let us first describe them.

Gravitation

The first quantitative theory of gravitation based on observations was formulated by Isaac Newton in 1687 in his Principia. He wrote that the gravity force that acts on the sun and the planets depends on the quantity of matter that they contain. It propagates to large distances and diminishes always as the inverse of the square of the distance. The formula for the force between two objects with masses m1 and m2 a distance r

away is thus

F = Gm1m2 /r2,

where G is a constant of proportionality, the gravitational constant. Newton was not fully happy with his theory since it assumed an interaction over a distance. This difficulty was removed when the concept of the gravity field was introduced, a field that permeates space. Newton’s theory was very successfully applied to celestial mechanics during the 18th and the beginning of the 19th century. Many scientists made a great contribution in finding a planet outside of Uranus, thus Neptune was found. A lot was done to calculate the precision of Mercury’s orbit, there were lots of discrepancies. It was not until 1915 that Albert Einstein could explain this discrepancy.

Galilei was the first to observe that objects seemingly fall at the same speed regardless of their masses. In Newton’s equations the concept of mass occurs in two different equations. The second law says that a force

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F on a body with mass m gives an acceleration a according to the equation F = ma. In the law of gravity, the force of gravity F satisfies F =mg where g depends on the other bodies exerting a force on the body (earth usually, when we talk of the gravity force). In both equations m is a proportionality factor (the inertial mass and the gravitational mass) and there is no obvious reason that they should be the same for two different objects. However, all experiments indicate that they are. Einstein took this fact as the starting point for his theory of gravitation. If you cannot distinguish the inertial mass from the gravitational one you cannot distinguish gravitation from an acceleration. An experiment performed in a gravity field could instead be performed in an accelerating elevator with no gravity field. When an astronaut in a rocket accelerates to get away from earth he feels a gravity force that is several times that on earth. Most of it comes from the acceleration. If one cannot distinguish gravity from acceleration one can always substitute the gravity force by being in an accelerating frame. A frame in which the acceleration cancels the gravity force is called an inertial frame. Hence the moon orbiting the earth can instead be regarded to be an accelerating frame. However this frame will be different from point to point since the gravity field changes. The principle that one can always find an inertial frame at every point of space and time in which physics follows the laws in the absence of gravitation is called the Equivalence Principle.

(Compiled from http://nobelprize.org/nobel_prizes/physics/articles/brink/index.html)

2. Find equivalents for the following phrases in Text 7A.

Которые удерживают материю вместе; удерживают нас на земле; на орбите вокруг земли; оказывать давление, действовать; такие как; основные составляющие; столкновение электронов с протонами; в том же самом процессе; позвольте нам сначала описать их; обратно пропорционально квадрату расстояния; постоянная сила тяжести (гравитационная постоянная); механика небесных тел; лишь только в; по-видимому; независимо от их масс; зависит от других тел; нет очевидной причины; которая в несколько раз превышает силу тяжести на земле; инерциальная система координат; в каждой точке пространства и времени; принцип эквивалентности.

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3.Read the passage a second time and answer the following ques-

tions

1.What are the basic features in physics (according to the text)?

2.What kinds of forces are presented in the text?

3.What are the ultimate constituents of matter?

4.What did physicists uncover by colliding proton to proton?

5.What was Calilei first to observe?

6.What did Einstein take as a starting point for the theory of gravita-

tion?

7.Why is it necessary to distinguish gravity from acceleration?

IV. Class Exercises

1. Fill in the gaps with one / ones.

1.Some substabces can attract metals. The _______ we use to make magnets are iron, nickel and cobalt.

2.A deuterium atom has a proton and a neutron. Which of these two nucleons is the _______ without a charge?

3.Which force is the ______ that holds the atmosphere in space?

4.Among scientists, physicists are the ______ who are trying to unify all the forces.

2. Translate the following abstract into Russian.

Electromagnetism and gravity are two basic forces of nature. They are very similar and students are trying to unify them. Electromagnetism works in small objects – it attracts the electrons from the atomic nucleus and maintains them in place. Gravity works with big objects – the pull of gravity from the nucleus of the Earth, spin and generate an electric and a magnetic field around them. These fields make up our planet's electromagnetic shield.

All our senses work with electric impulses from and to the brain. These impulses create an electromagnetic field inside our body. Is there an electromagnetic shield around us?

3. Now, continue translating from Russian into English.

Сила тяжести формирует облака газов и эти облака становятся звездами галактиками. Звезды создают (с помощью тепла) ядра ге-

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лия, углерода, кремния и железа, которые в свою очередь создают звездную пыль. Эта пыль составляет астероиды и планеты.

Некоторые космологи не согласны с этой теорией. Они объясняют, что расширение вселенной ускоряется. Другая теория говорит, что вселенная находится в постоянном воспроизводстве. Это означает, что имеются бесконечные “ вселенные”. Нет одной абсолютной теории, а есть важное наблюдение, что вселенная работает в ритме расширения и сжатия. У вселенной есть один основной компонент – энергия. Все формы от атома до пород, растений и людей – это различные аспекты одной и той же энергии.

V.Reading 7B

1.Before reading the text answer the following questions:

What is the difference between gravitational force and electromagnetic force, if any?

If we compare the gravitational and the electromagnetic forces between two objects, which force will be bigger?

Now read the text and check your answers.

Electromagnetism

It was James Clark Maxwell who, in 1865, finally unified the concepts of electricity and magnetism into one theory of electromagnetism. The force is mediated by the electromagnetic field. The various derivatives of this field lead to the electric and the magnetic fields, respectively. The theory is not totally symmetric in the electric and the magnetic fields though, since it only introduces direct sources to the electric field, the electric charges. A fully symmetric theory would also introduce magnetic charges, (predicted to exist by modern quantum theory but with such huge magnitudes that free magnetic charges must be extremely rare in our universe). For two static bodies with charges e1 and e2 the

theory leads to Coulomb’s Law giving the force between the two bodies

F = ke1e2 / r2,

where again k is a proportionality constant. Note the resemblance with Newton’s law of gravity. There is one difference though. While the gravitational force always is attractive, the electromagnetic one can also be repulsive. The charges can either have negative signs such as for the

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electron or be positive as for the proton. This leads to the fact that positive and negative charges tend to bind together such as in the atoms and hence, screen each other and reduce the electromagnetic field. Most of the particles in the earth screen each other in this way and the total electromagnetic field is very much reduced. Even so we know of the magnetic field of the earth. Also in our bodies most charges are screened so there is a very minute electromagnetic force between a human being and the earth. The situation is very different for the gravity field. Since it is always attractive, every particle in the earth interacts with every particle in a human body, setting up a force which is just our weight. However, if we compare the electromagnetic and the gravitational forces between two electrons we will find that the electromagnetic one is bigger by a factor which is roughly 1040. This is an unbelievably large number! It shows that when we come to microcosm and study the physics of elementary particles we do not need to consider gravity when we study quantum electrodynamics, at least not at ordinary energies.

VI. Reading 7C

Before reading the text answer the question:

What are the strong and the weak nuclear forces responsible for?

Upon reading the text check your answer.

Nuclear Forces

Since there were only two basic forces known in the beginning of the 20th century, gravitation and electromagnetism, and it was seen that electromagnetism is responsible for the forces in the atom, it was natural to believe that it was also responsible for the forces keeping the nucleus together. In the 1920s it was known that the nuclei contain protons, in fact the hydrogen nucleus is just a proton, and somehow it was believed that electrons could be involved in keeping the protons together. However, an idea like this has immediate problems. What is the difference between the electrons in the nucleus and the ones in orbit around the nucleus? What is the consequence of Heisenberg’s uncertainty relation if electrons are squeezed into the small nucleus? The only support for the idea, apart from there being no other known elementary particles, was that in certain radioactive decays electrons were seen to come from

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the nucleus. However, in 1932 James Chadwick discovered a new type of radiation that could emanate from the nuclei, a neutral one and the experiment showed that there are indeed electrically neutral particles inside the nuclei, which came to be called neutrons. Soon after Eugene Wigner explained the nuclei as a consequence of two different nuclear forces. The Strong Nuclear Force is an attractive force between protons and neutrons that keep the nucleus together and the Weak Nuclear Force is responsible for the radioactive decay of certain nuclei. It was realized that the strength of the two forces differed a lot. The typical ratio is of the order of 1014 at ordinary energies.

1. Guess if the following statements are true or false.

1.A needle is a magnet _____

2."Like" magnetic poles attract ______

3.The centre of the Earth is a magnet ______

4.Electromagnetic force holds our body together ______.

VII. Home exercises (to be done in writing)

1. Translate this part of an article from English into Russian.

Strong Interactions

A natural idea now was to search for a mechanism like the one in electromagnetism to mediate the strong force. Already in 1935 Hideki Yukawa proposed a field theory for the strong interaction where the mediating field particle was to be called a meson (now it is called a pion).

However, there is a significant difference between the strong force and the electromagnetic one in that the strong force has a very short range (typically the nuclear radius), This is the reason why it has no classical counterpart and hence had not been discovered in classical physics. Yukawa solved this problem by letting the meson have a mass. Such a particle was also subsequently seemingly found from cosmic rays by Carl Anderson. The discovery of nuclear fission in the late 1930’s led to an enormous interest in nuclear physics and in the war years most physicists worked on problems with fission so it was not until after the war that Yukawa’s ideas were taken up again. It was then

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realized that the particle found by Anderson could not be the meson of strong interactions, since it interacted far too little with matter, and it was then shown that this particle, now called the muon, is heavy cousin of the electron.

2. Translate this article from Russian into English.

Также в результате рассеяния протонов, кроме пионов, были произведены новые сильно взаимодействующие частицы, которые были названы адронами, некоторые из них имели время жизни в

10–8 до 10−10, а некоторые в 10−23 сек. Murray Gell-Mann предполо-

жил, что все сильно взаимодействующие частицы на самом деле являются пограничными состояниями (bound states) даже более фундаментальных состоянии, т.е. кварками. Идея была подтверждена в конечном итоге в Станфордском эксперименте в 1970 г. Чтобы понять силы внутри ядра, необходимо понять теорию поля для кварков. Чтобы понять силы, действующие между кварками, мы должны обсудить другую силу, слабые взаимодействия.

VIII. Basic English

The E-mail

1.Before reading the dialogue Answer the following questions

1.Why is Sam using Denisa's computer?

2.What does Sam do to Denise's computer?

Denise: Oh no, I hope you haven't wiped off (уничтожить) my hard drive (накопитель). I'll kill you if you have. What exactly was this "important message"?

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Sam: Well, it had something about "Pamela Anderson". Denisa: Well, why didn't you just delete it? Sam: It also said something about some photos. Denisa: And you opened it? Are you mad?

Sam: But it said they were from Pamela Anderson …

Denise: Gert out of here! (убирайся отсюда!)

3. And now listen to the dialogue (From "Cool English N 16", track 17)

Unit 8

I. Grammar: The Subjunctve Mood

Subjunctive Mood (Сослагательное наклонение)

Сослагательное наклонение служит для выражения действия предполагаемого, желаемого, маловероятного, или нереального.

Ex. 1. Read the following extracts. Pay attention to the underlined grammar forms.

1) Now it is essential that astronomers (should) determine the mass of large numbers of other objects in the Universe. There is the Moon, for instance, Earth's one satellite, which is 384,000 km from us (1 km is = 5/8 mi) and which circles the Earth once every 27 1/3 days. More precisely both the Earth and the Moon circle a common center of gravity. (2) The laws of mechanics require that the distance of each body from that center of gravity (should) be related to its mass. In other words, (3), if they were one half as massive as the Earth it would be two times as far from the center of gravity as the Earth is, if it were one third as massive as the Earth, it would be as far; and so on. (After Isaac Asimov "The Collapsing Universe".)

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