English book 1st year FEA

lot of branch scientific research institutions are placed in the capital.

Kiev is also a great educational and cultural centre of Ukraine. It is a real city of students, nearly 300000 students study at different higher schools, technical and specialized secondary schools in Kiev. Kiev's cultural life is rich and varied. Kiev has many fine museums, such as: the State Historical Museum, the T. G. Shevchenko State museum, the State museum of Ukrainian Applied Art, the State museum of Russian Art, Zoological museum etc. The National art of Ukraine is exhibited in the Museum of the Ukrainian Art. The famous T. G. Shevchenko Opera and Ballet Theatre, the Ivan Franko Ukrainian Drama Theatre, the Lesya Ukrainka Russian Drama Theatre and a lot of other theatres are greatly appreciated by Kievites and guests from other towns and countries.

The city's histor y is rich in glorious and tragic events. It repelled numerous enemy attacks, rose from the ruins and became more and more beautiful. During the Great Patriotic war Kiev was greatly ruined, it was liberated from fascist occupation on November 6, 1943. For the heroism displayed by Kievites in the struggle against the fascist invaders Kiev was awarded the title of Hero-city. There are many monuments in Kiev associated with the Great Patriotic war, such as: the Monument to General M. F. Vatutin, the Obelisk of Glor y at the tomb of the Unknown Soldier in the Park of Immortal Glory, the Museum of the Great Patriotic war with Statue of Motherland on it, the Victor y Memorial at Pobeda Square and others. Day by day Kiev becomes more and more beautiful. Kiev is an ancient but ever young city. Kievites are proud of Kiev.

III. Exercises.

Ex. 1. Read aloud and in a rush tempo the part of the text about:

a)historical monuments of Kiev;

b)Kiev during the Great Patriotic war;

c)Kiev as an educational and cultural centre.

Ex. 2. You show your town to English speaking visitors. What would you say about its foundation?

Ex. 3. You are a guide and take foreign guests on a sightseeing route about the most interesting places. What would you show them in the first place?

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10. The engineers will discuss the advantages of this new system.

11. He has graduated from the Moscow University. He graduated from the Moscow University in 1978.

12. My friend has already published the results of his discover y.

VII. Put all possible questions to the following sentences.

1. The applied sciences use the methods and principles of science to solve technological problems.

2. This text has dealt with the exact sciences and the descriptive sciences.

3. Physics is an exact science.

VIII. Put 5 questions to the Text. Ask your partner the question.

IX. The text contains three main ideas. Divide the text into three logical parts and say briefly what each part is about.

X. Retell the text.

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Unit 2

Grammar: Indefinite, Continuous, Perfect Tenses (Passive).

Modal verbs.

Pre-text Exercises.

I. Practise reading of the following words:

Coal [koul], source [s :s], however [hau’ev∂], efficient [ı’fı-

ous [’deındzr∂s], injure [’ındz∂], surface [s∂:fıs] , controversial [,k ntr∂’v∂:∫∂l].

II. Try to memorize the following words:

source - джерело, to provide - забезпечувати, to increase -

збільшувати, to support - підтримувати, oil - нафта, solar - сонячний, geothermal - геотермичний, cell - батарея, device - обладнання, expensive - коштовний, to drill - бурити, to pipe

-качати, waste - використаний, controversial - спірний fossil

-корисна копалина, fuel - паливо, to damage - псувати, руйнувати, pollutant - забруднювач, coolant - охолоджувач, safety - безпека.

THE SOURCES OF ENERGY

Fire, water, wind, coal, and oil are important sources of energy. They provide electricity. Because the world population is increasing, and because industry and. technology are growing, additional supplies of energy are needed to support today's industrial civilization. Some energy sources, such as oil and gas, are hard to get and expensive, however. Others are not yet efficient. The development of alternate sources of energy is an impotant goal of today's scientists and technologists.

Solar energy comes from the sun's heat. Large panels are used to collect the heat brought to the earth by the rays of the sun. Solar energy can be used to heat water and homes and to generate electricity.

8 applied art - ужиткове мистецтво

to appreciate (-ed, -ed) - високо цінувати labour - праця

to interrupt (-ed, ed) - переривати invader - загарбник

to display - виявляти tomb - могила

glor y - слава immortal - вічний pride - гордість

II. Read and translate the text "Kiev - the capital of Ukraine".

Kiev - the capital of Ukraine

The ancient city Kiev is the capital of the independent sovereign Ukraine, its political, administrative, scientific, industrial, educational and cultural centre. It is one of the most beautiful cities in the world. Kiev lies on the picturesque banks of the Dnipro river. Khreshchatik is the main thoroughfare of the city.

About three million residents inhabit the Ukrainian capital. Kiev is one of the oldest cities in Europe, it was founded in the fourth century. Therefore, it's no wonder, that there are a lot of ancient places of interest in our city. Among them we can see the Klevo-Pechersky Monaster y (Lavra), the Vydubitsky monastery, the Golden Gate, the Mariinsky Palace, the Andriivska church, the Kyr ylivska church, the Monument to Prince Volodymyr, the monument to the famous Ukrainian statesman and military leader Bogdan Khmelnitsky, the Volodymyrsky Cathedral and others. The St. Sophia Cathedral built in the eleventh century is one of the most distinguished monuments of ancient architecture.

Kiev became the capital of Ukraine in 1934. Kiev's monuments of the past are integrated with modern buildings - attractive hotels, cinemas, TV tower, metro stations, etc. At present Kiev is a large industrial centre of Ukraine. Lots of different plants and factories are located in this city. Complex automatic lathes, cameras, excavators, motorcycles, river boats, electrical measuring instruments and many other goods are produced at Kiev's enterprises. Kiev is known as a large scientific centre too. The Ukrainian Academy of sciences and a

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Ex. 8. Translate the following sentences from Ukrainian into

English you will be given in the control paper.

1.Україна проголосила свою державну незалежність на Сесії Верховної Ради 4 серпня 1991 року.

2.Наша держава дуже багата на корисні копалини.

3.Україна є членом О рганізації Об'єднаних Націй.

4.Україна є одн а з найбільш розвинутих країн співдружності незалежних держав.

5.Наша країна володіє багатою матеріальною та технічною базою.

6.УкраЇнські вчені збагати ли світову науку своїми відкриттями в різних галузях техніки та науки.

7.УкраЇнська література та м истецтво відомі на всіх конт и- нентах світу.

8.Столиця України Київ є одне з найкрасивіших міст у Європі.

9. Наша держава підтримує тісні культурні зв'язки з б а- гатьма країнами світу.

10. Зовнішня політика нашого уряду спрямована на зміцнення миру та безпе ки у всьому світі.

KIEV – THE CAPITAL OF UKRAINE

I. Memorise the following words and word combinations:

picturesque banks - мальoвничі береги

to occupy (-ed, -ed) - займати, окуповувати building - будова

resident - мешканець, житель historian - історик

church - церква cathedral - собор ancient - стародавній

to greet (-ed, -ed) – вітати envoy - посланець

to approve (-ed, -ed) - схвалити decision - рішення reunification - возз'єднення

to integrate - становити одне ц iле lathe - токарний верстат

camera - фотокамера /апарат/ measuring - вимірювальний enterprise - підприємство

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Although solar energy can be changed into heat, light, me-

chanical power, and chemical energy, there are problems in using it effectively. One pr oblem with solar energy is that many places often have dark, cloudy weather. How can power from the sun be collected in such places? One answer is the solar cell, which stores energy for use when there are no direct rays from the sun. Another problem is that, up to now, solar cells cannot provide energy as cheaply and efficiently as other devices can. For this problem there is at present no answer.

As oil becomes more expensive, more and more countries are turning to coal as a source of energy. The main difficult y with coal is that it pollutes the air. It may even be the source of "acid rain", which is rain containing harmful chemicals.

Geothermal energy comes from subterranean water. To get geothermal energy we must drill wells and pipe the hot water to the radiators in homes and factories. The problem is that geothermal energy is not available ever ywhere.

There is another way to use hot water for heating: to use waste heat and hot water from factories and mills.

One of today's most controversial subjects is nuclear or atomic power. In the past, fossil fuels such as oil and natural gas provided enough energy, but now they are harder to get and more expensive. People in developing countries need cheap energy for better lives. People in industrialized countries want to keep their high standard of living. Nuclear power can provide energy for both these purposes.

However, many people oppose atomic energy. They say nuclear power can be dangerous. A single accident could kill or injure thousands of people.

A strong argument of the proponents of nuclear energy is that it is clean. Uranium mines do not damage the land as surface coal mines do. Coal-and oil-powered industries excite ugly, bad-smelling pollutants; nuclear generators do not. However, opponents of nuclear energy point out that nuclear reactors pour coolants into streams and rivers. These coolants change the temperature of the water. Opponents state that the temperature changes cause damage to fish and plants.

The safety question is the most important of all. Ever y nuclear generator has radioactive waste products. Those opposed to atomic power say that this waste is dangerous, because it is hard to find safe places in which to store it.

9 Exercises.

I. Put the letter of the correct expression in the blank before each number.

II. Say whether the following statements are true or false:

1. Oil is considered an alternate source of energy.

2. Coal, the sun, and the wind are sources of energy. 3. Solar energy is cheap and efficient.

4. The sun's heat can be collected by panels.

5. Photo cells can be used in places with dark, cloudy weather. 6. "Acid" rain results from the use of solar power.

7. The subject of atomic energy is highly controversial. 8. Fossil fuels come from the atmosphere.

9. Proponents of nuclear power say it is dangerous. 10. Coolants lower the temperature of river water.

11. An important problem of nuclear reactors is where to store waste products.

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Ex. 3. You are invited to participate in the International conference. What questions would you be asked by your foreign colleagues about Ukraine?

Ex. 4. You show your native city Kiev to English -speaking visitors. What places of interest would you like to show them in the first place?

Ex. 5. You have a close friend in Canada. What would you write him on the achievements of Ukraine in the field of industry and science?

Ex. 6. You are taking part in Institute's English Olympiad. How would you answer the question on the foreign policy of the Ukrainian State?

Ex. 7. These are the questions you might ask your groupmates about the Ukraine.

1. When did Ukraine proclaim its State Independence?

2. Does the Ukrainian people mark this day as the national holiday?

3. When did All-Ukrainian Referendum take place?

4. How man y states are there in the Commonwealth of the Independent States?

5. What territory does Ukraine cover?

6. How many people inhabit this state?

7. Where are mountains situated?

8. Is the most of Ukraine's territory covered with mountains? 9. What are the main sea ports of Ukraine?

10. What is Odessa famous for?

11. How many lakes and water reservoirs are there on the territor y of the State?

12. What city is the capital of Ukraine?

13. What is this state rich in?

14. What does the Ukrainian State produce?

15. Did Ukrainian scientists enrich the world science with their discoveries?

16. Does this state take an active part in the work of different international organizations?

17. Is Ukraine the member of the United Nations?

18. What is the foreign policy of the Ukrainian government directed to?

ore, potassium, salt and other mineral resources.

Ukraine possesses a big metallurgic, machine-building, fuel end power base; it is a producer of chemicals and agricultural raw materials.

Ukraine produces planes and ocean liners, locomotives and carriages, tractors and combines, excavators and cars, up-to- date lathes and different instruments, electronic microscopes and TV-sets, computers and synthetic diamonds.

Scientists of Ukraine enriched the world science with important discoveries and inventions. They do significant research work in biology, medicine, nuclear physics, in the exploration of semiconductors, in the electric welding. A great contribution is made by Ukrainian literature and art which are rapidly developing. The best works of the Ukrainian literature and theatrical, musical and decorative arts are well-known the world over on all the continents.

The Ukrainian State is a member of the United Nations and takes an active part in the work of various international organizations. The Ukrainian Society for Friendship and Cultural Relations with Foreign countries maintains ties with hundreds of organizations and public figures of many states all over the world. The International activities of Ukraine and its Government are directed towards realizing the foreign policy of peaceful coexistence of states with different social systems, a policy aimed at strengthening peace and security in the whole world.

III. Exercises

Ex. 1. Read aloud and in a good tempo the part of the text about:

a)the Ukraine's State Independence;

b)industrial production in Ukraine;

c)participating Ukraine in different organizations.

Ex. 2. You meet foreign guests arriving in Ukraine for a short visit. What would you tell them about?

a)the Act of the Ukraine's Independence;

b)the natural conditions of Ukraine;

c)its sea ports;

d)dendro-parks in Ukraine.

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III. Compare and contrast:

IV. Answer the following questions to the text:

1. What sources of energy provide electricity?

2. Why are additional supplies of energy needed?

3. What is an important goal of today's scientists and technologists?

4. Where can solar energy be used?

5. What are the problems in using solar energy?

6. Why are more and more countries turning to coal as a source of energy?

7. How do they get geothermal energy?

8. What is another way to use hot water for heating? 9. Why do many people oppose atomic energy?

10. What is a strong argument of the proponents of nuclear energy?

V. Read the following; fill in the blanks with modal verbs:

A. How many people can the room seat? B. The room _______ seat 30 people.

A. Can your brother read English books without using a dictionary?

B. Yes, he __________. He knows English well.

A. May we use the glass tubes for the tests with these liquids? B. No, you __________________________.

A. May we cross the street here?

B. Oh, you _______________ do this. It is ver y dangerous,

VI. Translate the sentences. Pay attention to the modal verbs, functions of the verbs "to be", "to have":

1. First you must study the laboratory instruction and only then you can begin the experiment.

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radio station.

10. Our aim is to accomplish this task as soon as possible. 11. Smoking is dangerous.

12. They have already passed the exams.

13. He had to work hard to complete the work in time.

14. -Must we go to the institute today? -No, you need not. 15. This device can fulfil this operation.

VII. Read the following sentences and say which of them are in the Active and which are in the Passive Voice. Translate them.

1. Trains, airplanes and ships are equipped with various electronic devices.

2. Many thousand years ago the Greeks also used a foot measure.

3. At the institutes the students are taught many different subjects.

4. The academic year is divided into two terms. 5. The first iron bridge was built in 1778.

6. The student was asked many questions at the examination of physics.

7. At present they are studying various aspects of this problem. 8. The student was carrying out this experiment for twenty minutes.

9. This text has just been translated.

10. This question has already been discussed at the conference. 11. This problem will be dealt with in the next chapter.

12. Now solar energy is being studied by a lot of research groups.

VIII. Read the dialogue; fill in the blanks:

A. Do you know that up to the latest decades two systems of 12

II. Read and translate the text "Ukraine".

Ukraine

Ukraine proclaimed its State Independence at the Session of the Supreme Council (Verhovna Rada) on the 24t h of August 1991. The All -Ukrainian Referendum taking place on December 1, 1991 has corroborated the decision of the Ukrainian Parliament. More than 80% of the residents of the Ukrainian State have voted for its State Independence. The President of the Independent Ukraine has been elected. Since 1992 August 24-th has been market, as the nation-wide holiday of the Ukrainian Independence. At present Ukraine and ten former Soviet Republics (except Baltic State and Georgia) have formed the Commonwealth of the Independent States (C.I.S.)

Ukraine has its organs of state power and administration, its political, public and cultural organizations. It covers an area of 603,703 square kilometres. Most of its territor y consists of plains. Mountains are situated in the West and South of the country. The highest peak is Hoverla (2,061m) in the Carpathians. Crimean mountains are in the South and are not high.

The Southern part of Ukraine is washed by the Black Sea and the Sea of Asov. The main sea ports are Odessa, Kherson, Kerch, Sebastopol and Yalta, Odessa being the largest port on the Black Sea. This Hero-city is famous for its heroic defence against the fascist invaders during the Great Patriotic war.

There are some rivers on the Ukrainian land, the largest among them being the Dnipro. There are more than 2500 lakes and water reservoirs in Ukraine. The Kakhovka and Kremenchug artificial seas are the largest on the territory of Ukraine.

Many fine dendro-parks cover the territory of Ukraine, the most famous among them being Sofievka and Trostyanets. Askania Nova is a well-known reservation where many rare animals and birds live in natural conditions.

The population of Ukraine is more than 40 million people. Different nations and nationalities inhabit this state.

The Hero-city of Kiev is the capital of the Independent Ukraine. It is a great political, administrative, industrial, scientific, cultural and educational centre with a population of approximately three million inhabitants.

Ukraine is rich in iron ore, coal, natural gas, oil, manganese 69

decide to establish? 3. What did he find out? 4. When did the

needle deflect? 5, Who repeated Oersted's experiments? 6. Do you know Ampere’s rule? 7. What did Ampere establish and prove? 8. When is magnetism greatly increased? 9. Is the magnetic effect produced when the charges are at rest? 10. What is an electromagnet? 11. When does the iron core act as a magnet?

X. Give a short summary of Text 13.

UKRAINE

I. Memorize the following words and word combinations:

to proclaim – проголошувати independence – незалежність

to corroborate - підтверджувати decision - рішення

resident

inhabitant житель commonwealth – співдружність water reservoir – водосховище

rare animals and birds - рідкісні тварини та птaхи approximately - приблизно

manganese ore - марганцева руда potassium - калій

mineral resources - корисні копалини up-to-date lathes - сучасні вepтати semiconductor - напівпройідник

electric welding - електричне зварювання to maintain ties - підтримувати зв'язки carriage - вагон

synthetic diamonds - штучні алмази to enrich - збагачувати

rapidly - швидко

peaceful coexistence - мирне співіснування

to strengthen peace and security - зміцнювати мир та безпеку

measure were in use?

B. Yes ______________________. They were the metric system and the English one.

A. Is the so-called English system of measure widely used today?

B. No, ___________________, As far as I know the CLS system was preferred in most countries.

A. Was the system used in France?

B.Yes, _______________. However, it is interesting to note that the meter was first proposed by the French government in 1799, but the metric system in France was introduced only in 1840.

A. And what system is used in the United States?

B. Although the United States used the English system of measure, American scientists also used the metric system, as well as CLS system.

A. Why is it so?

B.The metric system has advantages over the English, for its divisions are based on the multiple of ten. This makes computation ver y easy,

IX. Put 5 questions to the Text. Ask your partner the questions.

X. Imagine that you are to make a report. While preparing it use the following plan:

1. Three kinds of energy.

2. Their sources.

3. Their advantages.

4. Their disadvantages.

UNIT 3

Grammar: Passive Voice. Degrees of Comparison.

Pre-text Exercises.

I. Practise reading of the following words:

property [’prop∂tı], although [o:l’ð∂u], structure [’strΛkt∫∂], comparatively [k∂m’pær∂tıvlı], electron [ı’lektron], neutron [’nju:tron], particle [’pa:tıkl], measuring [’mez∂rıŋ ], equal

[’i:kw∂l].

II. Try to memorize the following words:

to take part in - брати участь, to differ from - відрізнятися, in spite of - незважаючи, to consist of, to be composed of, to be make up of – складатися з, to carry (an electrical charge) -

нести (ел. заряд), to define - визначати, definition -

визначення, familiar - знайомий,відомий, negative - негативний, positive - позитивний, neutral - нейтральний, structure - структура, to weigh - важити, weight - вага.

III. Read the text below to find answers to the following questions:

1. Two definitions of an atom are given. What are they?

2. According to the passage what does an atom consist of? 3. How big is an electron compared to a neutron?

4. What was Thomson's concept of the structure of the atom? 5. What was Rutherford's concept of the structure of the atom?

THE STRUCTURE OF ATOM.

One definition of an atom is that it is the smallest part of an element that can take part in a chemical reaction. It is also defined as the smallest part of an element which has all the properties of that element. It follows from this second definition that atoms of silver differ from atoms of lead, that atoms of lead differ from those of gold, and so on.

Although atoms of different elements are different from each other, they all have a similar structure. Thus, all atoms consist of comparatively heavy nucleus around which one or

14

rest is much simpler than that of the bodies that are in motion 6. There was a time when lightning was a problem that scientists tried to solve but at present ever ybody knows that it is an electric spark like that produced by the electric machines.

7. Experiments show that all gases expand when heated.

VII. Translate the following sentences paying attention to the underlined words.

a) 1. Ampere’s contribution to electrodynamics as he called the new science began in 1820. 2. As it is impossible to detect electricity by our physical senses, we generally detect it by its effects. 3. An electromagnet loses its magnetic properties as soon as the current is turned off. 4. In certain branches of industry, chemical energy is not so widely used as mechanical energy. 5. The average speed of all molecules remains the same as long as the temperature is constant. 6. In order to produce electricity more economically the generators must be as large as possible. 7. As a gas is cooled, it loses heat as well as energy. 8. The magnetic effect of an electric current is the subject of the present article, as for the heating effect it was dealt with before.

b) 1. Rubber is a ver y poor conductor of electricity. 2. This is the ver y appliance which I need for my experiment. 3. Lomonosov was born in the family of a poor peasant. 4. All metals are poor insulators of electric current. 5. The United States is a great country. 6. Next summer I shall have a rest in the country. 7. The rest of the stor y should be translated at home. 8. Electricity at rest or in a static condition does no work. 9. Heat causes many chemical reactions. 10. What causes the electrons to flow along the wire? 11. A short circuit may be the cause of fire.

VIII. Give suitable prepositions to the following verbs and form sепtеnсеs with the Infinitives obtained.

to equip, to depend, to соmрaге, to consist, to contribute, to be interested, to be familiar, to point, to look, to start, to speak

IX. Answer the following questions

1. When was the voltaic cell invented? 2. What did Oersted 67

It is not difficult to understand that the greater the number of turns of wire, the greater is the m.m.f. (that is the magnetomotive force) produced within the coil by any constant amount of current flowing through it. In addition, when doubling the current, we double the magnetism generated in the coil.

A solenoid has two poles which attract and repel the poles of other magnets. While suspended, it takes up a north and a south direction exactly like the compass needle. A core of iron becomes strongly magnetized if placed within the solenoid while the current is flowing.

When winding a coil of wire on an iron core, we obtain an electromagnet. That the electromagnet is a controllable and reliable magnet is perhaps knows to ever yone. It is, so to say, a temporary magnet provided by electricity. Its behaviour is very simple. The device is lifeless unless an electric current flows through the coil. However, the device comes to life provided the current flows. The iron core will act as a magnet as long as the current continue to pass along the winding.

V. Fill in the blanks with suitable words given below. where, which, when, who, that

1. We know ... Oersted established the relation between the flow of electric current and a magnetic needle. 2. The great scientists Volta, Ampere and Yablochkov may be named among those ... have greatly contributed to electrical engineering. 3. The end ... the lines of force leave the coil after passing through its core will act like a north magnetic pole. 4. ... there is a certain connection between electricity and magnetism was proved by experiments. 5. ... he placed the wire parallel to the needle he saw ... the needle deflected. 6. A wire ... is wound in the form of a solenoid acts like a magnet as long as it is carrying a current.

VI. Translate the following sentences and define the functions of the word that.

1. It is clear that the greater the number of free electrons in a substance, the better that substance conducts the electric current. 2. An electric current passing through a wire heats that wire. 3. It is the unit of current that is named after Ampere. 4. That a solenoid has two poles that attract and repel the poles of other magnets is a well-known fact. 5. The physics of bodies at

66

more comparatively light electrons orbit. This nucleus is composed of one or more neutrons and one or more protons. Because these parts of an atom are smaller than the complete atom, they are called subatomic particles.

Compared to the size of the complete atom, the size of the nucleus is extremely small. In spite of its smallness, however most of the weight of an atom is concentrated in the nucleus.

Each electron, on the other hand, weighs only about 18001 of the weight of a proton or neutron.

There are other important differences between the subatomic particles that make up an atom. Each proton carries a single unit of positive electricity, while each neutron is electrically neutral, and each orbiting electron carries a single unit of negative electricity. Thus, since the number of protons in the nucleus of a complete atom is equal to the number of electrons, a complete atom is electrically neutral.

THE BEGINNING OF MODERN ATOMIC THEORY

In 1897, the British scientist J. J.Thomson discovered the subatomic particle that he named the electron. As a result of this discover y, John Dalton's theory that the atom is the smallest particle of matter (1808) was no longer acceptable. Thomson's new theor y of the structure of the atom was only partially correct, however. He described the atom as a solid, positively charged particle in which negatively charged electrons were embedded. The atom was electrically neutral, according to Thomson, because there were sufficient negatively charged particles (electrons) to neutralize the positively charged particle.

Between 1909 and 1911, Ernest Rutherford, a scientist from New Zealand, conducted a series of experiments which led eventually to the modern concept of the atom. In these experiments, a beam of positively charged alpha particles was directed against a thin sheet of gold in an evacuated glass tube. The huge deflections of the alpha particles led Rutherford to develop the following theories. First, he reasoned that each deflection was the result of the repulsive force between two positively charged particles. Second, he reasoned that because only 1 in 20,000 alpha particles was considerably deflected, each gold atom must consist mainly of empty space. Therefore, the nucleus of the gold atom must be minute, even in terms of

15

the size of an atom. Furthermore, the size of some deflections suggested that the nucleus was dense. Rutherford concluded that almost all the weight of an atom was concentrated in its nucleus. Around the heavy nucleus was a large area of empt y space in which the negatively charged electrons orbited.

Exercises

I. Study sentence 1, then complete sentences 2, 3, 4, 5, 6.

1. Paragraph 1 of the text gives two definitions of the atom.

2. Paragraph 2...

3. Paragraph 3...

4. Paragraph 4...

5. Paragraph 5...

6. Paragraph 6...

II. a) Change sentences 1-6 into questions.

b)Ask another member of class these questions. His answer must begin: "No ..."

Example: The electron was discovered by John Dalton. Was the electron discovered by John Dalton?

III. Make the object of the italicized verb in sentences 1-5 the subject of the verb.

Example: The sun heats the earth.

The earth is heated by the sun.

1. All objects radiate heat energy.

2. Two factors affect the rate at which heat energy is 16

charges. 5. That the unit of current is named after the famous French physicist Ampere is probably know to you. 6. When placing an iron core within a solenoid, we obtain an electromagnet. 7. The phenomenon Oersted pointed at interested Ampere greatly. 8. We know that the direction of the magnetic effect of the current can be found thanks to Ampere's rule. 9. If suspended so that it can rotate freely, the solenoid points north and south when the current flows.

Text 13. MAGNETIC EFFECT OF AN ELECTRIC

CURRENT

The invention of the voltaic cell in 1800 gave electrical experiments a source of a constant flow of current. Seven years later the Danish scientist and experimenter, Oersted, decided t o establish the relation between a flow of current and a magnetic needle. It took him at least 13 years more to find out that a compass needle is deflected when brought near a wire through which the electric current flows. At last, during a lecture he adjusted, by chance, the wire parallel to the needle. Then, both he and his class saw that when the current was turned on, the needle deflected almost at right angles towards the conductor. As soon as the direction of the current was reversed, the direction the needle pointed in was reversed too.

The north end of the needle moves away from us when the current flows from left to right. Oersted also pointed out that if the wire is adjusted below the needle, the deflection is reversed.

The above-mentioned phenomenon highly interested Ampere who repeated the experiment and added a number of valuable observations and statements. He began his research under

find the direction of the magnetic effect of the current. It is known as Ampere's rule. Ampere established and proved that magnetic effects could be produced without any magnets by means of electricity alone. He turned his attention to the behaviour of the electric current in a single straight conductor and in a conductor that is formed into a coil, i.e. a solenoid.

When a wire conducting a current is formed into a coil of several turns, the amount of magnetism is greatly increased.

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