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Assignment 5. Find the Infinitive in the text, define its function and translate sentences into Russian



Assignment 6. Translate the following sentences using the Infinitive construction:

 

1) Мы знаем, что тепловая энергия – это энергия молекулярного движения.

2) Известно, что молекулы движутся в различных направлениях.

3) В течение долгого времени считали, что тепло – это невесомое вещество.

4) Говорят, что молекулы воды движутся быстрее, когда ее нагревают.

5) Считают, что молекулы холодного вещества движутся медленно.

6) Известно, что при нагревании тела расширяются.

7) Студенты, наверное, понимают разницу между постоянным и переменным током.

8) Нам известно, что тепло может создавать изменение состояния вещества без изменения его температуры.

 

 

Assignment 7. Make up 4 sentences using the infinitive constructions according to the models given below.

 

Models: 1. I heard my friend speak over the radio.

2. My teacher wants me to speak English well.

 

 

Assignment 8. Arrange the following words given in Columns I and II in pairs of:

(a) antonyms: (b) synonyms:
I at rest solid fast useful charge hot dark negative the first increase wrong valuable II positive right the last decrease liquid in motion invaluable slow useless discharge cold light I to employ to make to travel different like to receive liquid   II to move similar various fluid to do to get to use  
       

Assignment 9.

(a) Form verbs from the following nouns:

 

increase, weight, statement, movement, difference, com­pression, collision, flow, application, requirement, knowledge, education, expansion

 

B) Use the verbs in sentences of your own.

Assignment 10. Translate the following sentences paying special attention to the underlined words:

 

1) The static charges are known to be at rest.



2) The alternating current changes its direction many times a second.

3) We know the electric charges to be positive and negative.

4) Some liquids are known to conduct current without any changes to themselves.

5) On the contrary the electrolytes are known to change greatly when the current flows through them.

6) One can charge dissimilar objects by rubbing them.

Assignment 11. Translate the following questions and answer them:

1) Что такое тепло?

2) Почему предполагали, что тепло – это невесомое вещество?

3 Могли ли люди наблюдать некоторые тепловые эффекты?

4) Что происходит благодаря трению и сжатию?

5) Какие тепловые действия (phenomena) установил Ломоносов?

6) Из чего состоит вещество?

7) Как называются мельчайшие частицы вещества?

8) Что происходит, когда тело нагревается?

9) Существует ли заметная разность температур между холодным и горячим телом?

10) Какой прибор используется для измерения температуры?

Assignment 12. Speak on the work of the following scientists using the words given below:

 

Franklin: to prove, unlike, charge, to rub, dissimilar, object, rubber, negative, glass, positive

Volta: continuous, current, to produce, the first, unit, electric, pressure, volt, voltaic, pile.

Lomonosov: to state, heat, phenomena, molecular, motion, atomic, theory, law, conservation, matter



Assignment 13. Read and translate the following story:

 

Heat and Cold

 

At a physics lesson the teacher asks the children about the effects of heat and cold on the body.

“Heat makes things bigger and cold makes things smaller,” answered a clever boy.

“Quite right,” says the teacher, “Can you give an example?”

“In summer, when it is hot, the days are longer, but in winter, when it is cold, the days are shorter,” answered the clever boy.

 

SUPPLEMENTARY READING

 

 

TEXT 1. THE STRUCTURE OF THE ATOM

 

The atom is the basic particle of all matter. All solids, gases, liquids are composed of atoms.

For a time the atom was considered to be indivisible, but then it has been found that the atom in its turn can be divided into many different components.

In dividing the atom the man releases forces of great magnitude. These are forces that bind the central core of the atom. This central core – the nucleus – is extremely small in diameter.

The nucleus of the atom is of a highly complex structure. It is the three main components of the atom that we shall deal with below. These are called protons, neutrons and electrons.

The proton carries a positive charge of electricity, the number of protons in the nucleus determining the element that the atom forms.

For example, if the nucleus has a single proton, then it will form the gas hydrogen, if 92 protons are present, the element will be uranium and so on. In short, if the number of protons in the nucleus is known, the element can be found out at once.

As mentioned above, the proton carries a charge of positive electricity. We know the bodies charged with the same kind of electricity to repel one another. When two protons are brought close together they repel one another with a great force.



The second of these basic components of the nucleus is the neutron. The neutron does not carry a definite electric charge. The sub-particles that form the neutron do carry charges but the charge of one balances that of another leaving the neutron neutral. It is from this state that it gets its name.

The third component of the atom is the electron. The electrons revolve around the nucleus. Each electron carries a negative charge of electricity that is equal to the positive charge of a proton in the nucleus.

As the charge of the electron is negative and that of the proton positive, it might be thought that the proton would attract the lighter electron and draw it into the nucleus. This would happen if the electron were not revolving around the nucleus.

The speed of the electron establishes sufficient centrifugal force so that it counteracts the neutral attraction. Thus the higher the speed of the revolving electron, i. e. the greater its energy, the farther from the nucleus it will revolve.

 

TEXT 2. PEACEFUL USES OF ATOMIC ENERGY

 

The splitting of the atom can either destroy all the achieve­ments of mankind all over the world or it can serve economic and cultural development of the peoples. Russia and other countries want the atomic energy to serve the peoples living on our planet.

There are three possible ways of using atomic fission, the most outstanding discovery of physics. These are: the use of radioactive isotopes, which are formed in nuclear processes, the use of powerful radioactive radiation, mainly in certain processes in organic chemistry, and the use of the energy released during the fission of uranium and plutonium nuclei.

All these three ways are being successfully developed in Russia.

The first in the world industrial atomic power plant with a 5,000 kW capacity was put into operation in the Soviet Union in 1954. This power generating installation based on the uranium graphite reactor was the creation of Kurchatov, an outstanding Soviet physicist.

Ten years later two more atomic power plants began gener­ating electricity, namely: the Beloyarskaya named after Kurchatov and the Novovoronezhskaya.

At the Beloyarskaya atomic power plant Soviet scientists have for the first time in the world achieved nuclear super­heating of steam directly in the reactor before feeding it into the turbine. This is a fresh contribution to nuclear engineering.

The projected capacity of the first section of the Novovoronezhskaya atomic power plant is 210,000 kW. The second sec­tion is known to have a capacity of 365,000 kW, This power plant has been linked to the single power grid of the European. part of the Soviet Union.

It is interesting to note that a 210,000 kW heat power plant consumes more than 2,000 tons of coal daily, whereas an atomic - power plant of equal capacity takes only about 800 grammes of Uranium-235.

There are great possibilities for the use of radioactive radiation in different radiation-chemical processes. For instance, radiation polymerization of various organic compounds, which makes it possible to produce materials with new qualities.

Radioactive isotopes are of great importance today. Several thousand research medical, agricultural and industrial organizations of our country make use of radioactive isotopes.

Russian scientists do their best to make the atom serve peace and progress and further develop the peaceful uses of atomic energy.

 

TEXT 3. NUCLEAR POWER STATION

 

Atomic energy was first used for the explosion of the atomic bomb in 1945. Few people realized at first that the same energy which can destroy an entire city so easily can also be harnessed for the good of mankind.

The first practical realization of this came with the an­nouncement in 1954, that a power station working on atomic energy had been put into operation in the USSR. The effect of this was to make people realize that nuclear power was not something in the remote future but was quite possible, because the technical problems had been solved.

A nuclear power station is similar to ordinary power sta­tions with the one exception, namely, instead of a coal-burn­ing furnace it has a nuclear furnace, i.e., heat is produced by nuclear fission in a reactor.

As for the first in the world nuclear power station men­tioned above, the fuel is uranium enriched 5 per cent with U-235. The pile is graphite-moderated and water-cooled. It generates 5,000 kW.

The pile can be cooled by many means, namely, by gas, water or liquid metal. The heat is applied to produce steam which in its turn is used to generate electricity.

The pile is controlled by a "moderator" that is, rods of cadmium or boron steel which absorb neutrons readily and so stop the chain reaction when they are inserted into the pile.

The reactors being built at present, consist essentially of uranium bars which lie in a number of channels drilled through blocks of graphite. The purpose of graphite can be explained if we imagine the fission process starting in a bar of uranium somewhere at the centre of the pile. The first fission releases neutrons enough to carry on the process and establish the chain reaction but they are moving so fast that they escape out of the bar of uranium in which they were born without giving rise to any further fission. Outside the bar the neutrons find themselves surrounded on all sides by graphite. Graphite, like heavy water, is what is known as a “moderator”, that is to say, it possesses the power of making neutrons lose energy, without absorbing them; so that by the time the neutrons have reached the other side of the graphite and come into contact with another bar of uranium, they are of just the right energy to promote fission within the bar. The graphite is made exactly of the right thickness for this purpose.

In our country it is the practice to enclose a large-scale reactor in a steel shell. Thus, if an accident should occur to the pile, there is no possibility of radioactive leakage. A further shell of concrete, the so-called biological shield, lies outside the steel shell. The function of this biological shield is to absorb radiation escaping from the pile so that no one should be injured by approaching the pile.

 

TEXT 4. POWER FROM THE ATOMS

 

Among the peaceful uses of atomic energy, perhaps the most important for its practical value is the production of power. At the present time most of the power we need is generated by burning coal and oil. We get these fossil fuels from deposits that were formed some 250 million years ago, under special weather conditions which have not occurred again on earth. When we mine coal or exploit oil wells, we use up reserves that will not be replenished.

At some future time all the coal and oil in the world will be used up, and this time may come sooner than we think; the demand for power is growing at an amazing speed, and to satisfy it we must burn more and more fuel. There are several reasons for the increase in the demand for power: the population of the world is growing very rapidly; many countries that were underdeveloped are now becoming industrialized; and standards of living are rising everywhere. As a result, more and more people consume more and more power in their homes, and they also want more and more goods made with machines that need power to run. The experts say that if the demand for power keeps growing at the present rate, the world reserves of coal and oil will last a few centuries, possibly only one hundred years.

It is fortunate that at this critical moment in human history, man has learned to generate power from atomic energy. Already several atomic plants are producing electricity; two atomic boats have been built; and atomic power is used experimentally to heat homes.

Electric power is generated from atomic energy in atomic power plants. In principle, an atomic plant is not very different from a regular plant generating elec­tricity from fossil fuels. A regular plant consists essen­tially of a boiler, a turbine, and a generator. In the boiler, coal or oil burns to develop heat which changes water into steam. The steam makes the turbine turn, and the turbine drives the generator. While running, the generator produces electricity, which is then sent into power lines and distributed where needed.

In an atomic power plant, a reactor – a modern atomic pile – takes the place of the boiler. When the reactor chain reacts and releases atomic energy, it becomes very hot. The heat thus produced changes water into steam. As in a regular power plant, the steam turns the turbine, and the turbine drives the generator. The generator produces electricity. So we may con­sider a reactor as a boiler that "burns" uranium or other fissionable materials. For this reason fissionable materials are now commonly called nuclear fuels. The most modern power plants now being built are entirely enclosed in round domes of steel or other materials that stop the passage of all radioactivity. These domes are meant to protect the population in case a reactor should not work properly and should let radioactivity leak out. In the future, the landscape all over the world may be marked by these round domes. Perhaps our children and grandchildren will consider them to be symbols of the atomic age, as we consider the tall smokestacks of our factories to be symbols of industrial progress.

Atomic power plants are still very expensive, as are all new things. When cars were first built, only rich people could afford them. Likewise, only rich countries can now afford large atomic plants. Yet many countries are constructing smaller plants in which their scientists and engineers can learn how to generate electricity from atoms and how to solve the difficulties that arise when reactors work to make atoms split.

 

The first atomic plant in the world to generate elec­tricity steadily and to send it out over power lines was built in the Soviet Union. It started working in June, 1954. The next year, at the first conference on the peaceful uses of atomic energy, the Russians showed models and a beautiful colour film of this plant.

As seen in the movie, the reactor was large and bulky. The nuclear fuel that "burned" in it was slightly enriched uranium. It was not scattered in chunks, as in the first pile built in Chicago, but was made into fuel elements. These are nuclear fuel which has been fashioned into long rods, plates, or tubes, and they are easily pulled out when needed. Fuel elements have been used in many reactors built after the Chi­cago pile.

The Russian reactor contained 128 fuel elements After it had worked for some time, the fuel elements were spent: many uranium atoms had split and many fission products had formed. These products absorbed many neutrons, and not enough neutrons were left to keep the chain reaction going. The spent elements were then pulled out by a huge crane and replaced by fresh ones. Men in white coats and caps operated the crane by remote control.

The Russian atomic plant generated 5,000 kilowatts of electricity. The movie showed how this electricity reached the consumers, and how it was used. It showed, for instance, cows being milked by atomic power on a Russian farm.

The second power plant that went into operation was built at Calder Hall, in England. In October, 1956, Queen Elizabeth II officially inaugurated it. She pulled a switch, and the electricity from the Calder Hall plant began flowing into the power lines. This plant generated ten times as much electric power as the first Russian plant.

In our country we did not build an atomic power plant of industrial size as early as England did, for there was a difference between the needs of the two countries. England expected a shortage of coal and oil in the near future and wanted to have another source of power as soon as possible. English scientists went ahead and built an atomic power plant with a type of reactor which they knew would work, because it had already been tried. (It was very similar to one of the atomic piles built in the United States during the war.) The United States had larger reserves of coal and oil, and more money than England. Because we had more coal and oil, we did not need a new source of power as soon as England. Because we had more money, our scientists could plan and build reactors of different types to see which would work better and cost less. In this country, many reactors of small size were con­structed with different materials, different nuclear fuels, different substances for slowing down neutrons and for carrying away the heat from fission.

Our scientists found that there was no "best" type of reactor, but that several seemed promising. Our government and industries chose the most promising types, and then embarked on the construction of several atomic power plants. The first to be completed was the plant at Shippingport, near Pittsburgh, Penn­sylvania. In the Shippingport reactor, the substance that slows down neutrons is water. Water was not used in the first atomic pile, because it captures more neutrons than graphite, but the Shippingport reactor makes up for the loss of neutrons in other ways; its fuel, for instance, is enriched uranium which is more fissionable and absorbs fewer neutrons than natural uranium. In this plant, the water that slows down neutrons also cools the reactor.

The Shippingport plant generates 60,000 kilowatts of electricity. It began working in May, 1958, when President Eisenhower sent an electronic impulse to Shippingport from the White House in Washington. The impulse opened a valve and started the electricity flowing through the power lines to the Pittsburgh area. A much larger plant was built at Dresden, Illinois, 50 miles southwest of Chicago. It went into operation in August, 1960, three and a half years after con­struction began, and it generates 180,000 kilowatts of electricity. A 190-foot steel sphere houses a boiling water reactor, in which the water that slows down neutrons and is heated by the energy released in fis­sion is allowed to boil and directly produce the steam that runs the turbine. Other large plants are under construction in the United States.

Other countries are now building or planning to build atomic power plants, and more countries will do the same as soon as they have trained their scientists and engineers in atomic science. The prospects for an atomic industry developing fast the world over are very good. Yet plans must be continuously revised to fit changing needs. Thus in England the price of oil and coal and the demand for power have not gone up as fast as it was thought they would, and in the summer of 1960 the British government announced that it was slowing down the pace of its atomic program.

In time, atomic power will help underdeveloped countries. In these countries there are large areas with­out railways or good roads, where it would be difficult to transport coal or oil. But nuclear fuels are much more compact than coal or oil; for one pound of uranium can do the work of more than one million pounds of coal. It may be possible to ship or fly enough uranium to run a reactor in places to which it would not be possible to transport enough coal or oil for a regular power plant.

The best type of reactor for distant areas may be a small "package" reactor which can be transported by air. When "package" reactors, which are now under study, become available at a reasonable price, they will help underdeveloped countries in many ways. In places that at present have no electricity, such reactors will supply power to develop small industries or to give light to towns. Near isolated mines, they will help extract ores from under the ground. In dry regions they will supply power to pump water for irrigation, and in marshy places they will help drain away the water. When these things come to pass, stretches of land that are now either deserts or marshes will produce food for undernourished populations.

 

Atomic power can be used to drive ships; for this pur­pose it has the advantage of being much more com­pact than any other fuel. Until the present time, stored fuels have always taken a great deal of space in large ships. In atomic ships, much of this space can be put to other uses, and the ship can make many trips with­out refueling.

The first two civilian boats propelled by atomic power have been built. In both, as in all future atomic boats, one or more reactors generate the heat needed to change water into steam, and the steam so produced drives the propellers.

The icebreaker Lenin of the Soviet Union has already gone to sea.

In July, 1959, at Camden, New Jersey, the merchant ship Savannah of the United States was launched in a typical ceremony by Mrs. Eisenhower, the President's wife. She smashed a white-clad bottle of champagne on the stem of the ship, giving the signal for the workmen to trigger the releasing machinery. Swiftly the Savannah slid down into the Delaware River. It is able to sail almost fifteen times around the world without refueling. Its floating laboratory will study any difficulties that may arise and try to solve the problems of atomic propulsion. The results will be extremely useful in the building of future atomic-powered merchant fleets.

 

The heat produced when a reactor operates may be used directly to heat buildings. At the first conference on the peaceful uses of atomic energy, this use of re­actors was among the topics discussed by scientists. A funny incident resulted. A woman who lived in Geneva read in the papers that atomic energy from uranium could be used to heat homes. She also read that the United States had set the price of natural uranium at forty dollars per kilogram, which is a little less than twenty dollars per pound. After a little figuring the woman came to the conclusion that uranium was quite an inexpensive fuel, and she went to the United States information desk at the conference to ask where she could buy uranium. The girls at the desk tried to ex­plain that she could not “burn” uranium easily, in her furnace, like coal. They added that uranium “burns” only in reactors and that reactors are very expensive. The woman insisted, "You don't know how high my heating bill runs!" She did not realize that the cost of a reactor may run into tens of millions of dollars.

When reactors are eventually used to heat buildings, one reactor will serve a section of a city or a whole town.

 

 

CONTENTS

 

 

UNIT ONE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT TWO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT THREE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT FOUR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT FIVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT SIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT SEVEN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT EIGHT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT NINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT TEN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT ELEVEN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Supplementary Reading  
TEXT ONE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TEXT TWO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TEXT THREE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TEXT FOUR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

 


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