The Kiev Polytechnic Institute 3 страница

The electrical force is similar to a gravitational force, acting across empty space, or rather an electromagnetic field. However, gravitation only attracts. Electrically charged substances either attract or repel. Finally, the electrical force is at work in all the processes of the body.

The remaining two forces are the nuclear forces that act only within the atom. Scientists divide them into two categories, the strong nuclear force and the weak nuclear force. The strong force is the one that acts on the nucleus of the atom to hold together the protons. Since the protons are positively charged, they repel each other and a very strong force is needed to hold them together. The weak force is the one responsible for certain types of radioactivity.

For a long time, it was thought that all events in nature could be explained by these four forces. Recently, however, scientists have discovered problems with this theory. For one thing, the gravitational pull deep in an Australian mine was found to be stronger than gravity on the surface of the earth. Also, some experiments have revealed differences in the rate certain objects fall toward the earth. To explain these differences, physicists have proposed that there may be a fifth force operating in the universe. This force, called hypercharge, is thought to be weaker than gravity and counter acts the force of gravity at short distances? So far, more experimentation is necessary before the hypothesis of a fifth force becomes accepted theory.

Exercises

I.Match the terms on the left with the information on the rigth. Then say a complete sentence about each term.

___1. Gravitation	a. act only within the atom
___2. Electromagnetic force	b. is at work in all processes of the body
___3. Electrical force	c. is the force by which all odi-es are attracted to each other
___4. Nuclear forces	d. is the powerful attraction of unlike electrical charge and repulsion of like charges.

could not he explained by the above theory, namely: the development of heat owing to friction as well as the temperature changes during the compression or expansion of a gas.

M.V. Lomonosov was the first to state that heat phenomena were due to molecular motion. His statement proved to be correct years after his death.

At present, we know heat to be a form of energy. Besides, we are quite familiar with the fact that all substances are made up of little particles called molecules. These are so minute that a single drop of water, for example, contains millions of them. Although a drop of water left on the table may seem to be at rest, everyone of its molecules is really moving about, colliding with other molecules in the drop of water.

What process takes place when we place a kettle full of cold water on the fire, in other words, when we want to heat water? The molecules begin to move much faster then, so that every time there is a collision, they jump away from each other much farther than they did before. As a result, the drop of water becomes larger, that is to say, it expands. In scientific language this property is called expansion.

The faster molecular movement makes the water first warm and then hot. On taking the kettle from the fire, we expect the molecules to slow down, and indeed the water begins to get cold. When the tea is said to be "hot" it really means that its molecules are travelling very fast. On the contrary, they are moving more slowly, when the tea is cold.

Heat and temperature are closely connected. To show that similar quantities of heat may produce different effects in different substances is not difficult at all. Placing a needle on the fire at the same time as a kettle of cold water, we find that the needle is red-hot before there is any marked difference in the water temperature.

One must say here that a red-hot needle receives far less heat than a kettle full of boiling water but its temperature is nevertheless much higher. But if we place it in the boiling water, although the latter is certain to possess far more heat than the former, the needle gives up heat to the water and not vice versa. When two bodies at different temperatures are brought into contact, we expect the warmer body to get cold while the colder one will be warmed. In this case, heat is said to flow from one body to the other by conduction.

As for expansion caused by heating, it is useless and even

IV. Study the table given below.

The Subjective Infinitive Construction	1. He is supposed to work at this plant. -   2. He seems to know English well. -
The Objective Infinitive Construction	1. We suppose him to work at this plant. -   2. I saw the water boil. -

V. Choose the sentences with: a) the Subjective Infinitive Construction; b) the Objective Infinitive Construction. Translate them into Ukrainian.

1. He is known to be a good scientist. We know him to be a good scientist. 2. His methods are said to be very interesting. They think his methods to be very interesting. 3. The meeting is expected to open at three. We expect the meeting to open at three. 4. Ann heard the secretary to say so. The secretary was heard to say so. 5. All his friends consider him to be a good speaker. He is considered to be a good speaker. 6. He is believed to know English. They believe him to know English. 7. The expedition is expected to return next month. We expect the expedition to return next month. 8, The shape of the device is said to be round. They say the shape of the device to be round. 9. The commander reported the enemy to have been beaten. The enemy was reported to have been beaten. 10. We know oil and coal to be the main kinds of fuel. Oil and coal are known to be the main kinds of fuel. 11. He seems to be ill. 12. We want you to wash the plates.

Text 12. WHAT IS HEAT?

What makes one thing hot and another cold? What do the terns "hot" and "cold" really mean?

Scientists are known to have worked for a long time to find an answer to the last question. They decided at last that the manifestation of heat was caused by a weightless substance or fluid called "caloric" which flowed from a hot body to a cold one. However, experience showed that certain heat effects

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

1. Gravitation keeps planet in their orbits.

2. Gravitation is the strongest of the four basic forces of nature.

3. The electromagnetic force causes friction.

4. The nucleus of an atom has a negative charge and electrons orbiting the nucleus have a positive charge.

5. Electrically charged substances only attract.

6. Electrically charged substances either attract or repel.

7. Scientists divide nuclear forces into two categories: the strong nuclear force and the weak nuclear force.

8. The gravitation pull deep in an Australian mine was found to be weaker than gravity on the surface of the earth.

9. More experimentation is necessary before the hypothesis of a fifth force becomes accepted theory.

III. Answer the following question:

1. What is one of the basic forces of nature?

2. What are four basic forces of nature?

3. Why are effects of gravitation strongly felt?

4. What force is responsible for binding the particles of an atom together?

5. Why aren't we aware of the electrical forces in normal life?

6. What force causes friction?

7. 'Why is electrical force similar to the gravitations force?

8. What's the difference between strong and weak nuclear force?

9. What problems have been discovered by scientists?

IV. Define the tense-forms of the verbs in the following sentences and translate them.

1. Lasers are now used for many scientific, medical and industrial purposes.

2. At present they are studying verious aspects of this problem.

3. Have you read anything interesting lately?

4. We had finished our work by 5 o'clock yesterday.

5. This equipment had been repaired before you came.

6. The engineers will discuss the advantages of this new sys-

tem.

7. The device will be working when you come.

8. We were provided with the necessary literature.

9. Our laboratory is housed in an old building.

10. The scientists were carrying out this experiment for twenty minutes.

11. We were looting for a more simple method of solution but could not find it.

12. They will have finished their work by lunch time.

V. Analyse the functions of the verbs "to be", "to have". Translate the sentences:

1. The substance that we are speaking about is water.

2. He will be an engineer in two years.

3. The process of cooling is to end in an hour.

4. At the end of the reaction we were to define the changes in the substances.

5. Automated systems have a number of advantages.

6. The scientist had to stop the experiment.

7. After the new device had been tested it was installed in our laboratory.

9. She will have many new subjects next term.

10. Telescopes are being used since their invention.

VI. Read the dialogues. Fill in the blanks:

a) A.... your sister study at the institute?
B. Yes, she....

A. What Institute... she study at?
B. She...at the Polytechnic Institute.
A.... your friends study there too?
B. No, they....... They... at the University.

b) A. This... my institute friend...
B.... she study in her first year?
A. Yes, she.... She... a first year student.

c) A. These... students of our institute,
B. What department... they study in?
A. They... in the evening department.
B. What... they do at the day time?
A. At the day time they... at the plant.

Unit 12

Grammar: The Subjective Infinitive Construction. The Objective Infinitive Construction.

Pre-text Exercises

I. Practise reading of the following words:

Another [∂’nΛð∂], term [t∂:m], cause [k:z], weightless [’weıt-lıs], certain [ks:tn], effect [ı’fekt], development [dı’vel∂p-m∂nt], compression [k∂m’pre∫(∂)n], expansion [ıks’pæn-∫(∂)n], molecular [m∂u’lekjul∂], death [deΘ], besides [bı’saıdz], quitе [kwaıt], molecule [’m lıkju:l], single [’sıŋgl], assume [∂’sju:m], although [:l ’ ð∂u], process [’pr∂uses], fiгe [’faı∂], collision [k∂lı z (∂)n], jump [d z Λmp], farther [fa:ð∂], tea [tı:], really [’rı∂lı], quantity [’kw ntıfaı], needle [’ni:dl], nevertheless [,nev∂ð(∂)’les], higher [’haı∂], while [waıl], other [’Λð∂], thermometer [Θ∂’m mıt∂].

II. Try to memorize English words and word-groups and their Ukrainian equivalents.

To cause - викликати, вимагати, призводити до; certain – деякий, певний; collision - зіткнення; compression - стиснення, стискання; conduction - проводність; development - розвиток; effect -дія, вплив, результат; expansion - розширення, збільшення; to expect - чекати, очікувати, розраховувати; to explain - пояснювати; friction - тріння; fire - вогонь, пожежа; to place - розміщувати, класти; quantity - кількість; to take place - траплятися, мати місце; term - термін.

III. Translate the words and their derivatives.

To cause - cause - causeless; certain - uncertain - certainly; effect - to effect - effective; expansion - to expand - expansive; to place - place - to displace - to replace; quantity - quantitative - quantitatively; collision - to collide.

energy. 4. Scientists are trying to solve the problem connected with the new electric phenomena. 5. The lightning conductor is a metal device to protect building from thunderstorms. 6. To carry on experiments with atmospheric electricity was very dangerous at that time. 7. To magnetize an object means to place it into the field of a magnet.

VI. Answer the following questions:

1. What types of electricity are there?

2. How do they differ?

3. What can you say about using the electricity obtained by rubbing object?

4. What did Franklin prove in 1753?

5. What Russian scientist might be mentioned in connection with the Franklin's discovery?

6. What was Galvani the first to observe?

7. What scientist was the first to get the electric current?

8. The unit of electric pressure is named after Volta, isn't it?

9. What did Voltaic pile consist of?

10. In what year was a continuous current generated for the first time in the world's history?

11. What facts of Volta's biography do you remember?

VII. Divide Text 11 into logical parts and find the topical sentences in each part.

VIII. Retell the TEXT 11.

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

VIII. Retell the text.

IX. Task 1. Rend the following text.

Mathematical Signs and Symbols.

Signs and symbols are very important in mathematics. Using them we can write mathematical expressions in a very short form. Here are some mathematical signs and symbols the English names of which you masts know.

The symbol + (plus) stands for add. It is a plus sign. (As in the equation 3 + 5 = 8).

The symbol - (minus) stands for subtract. It is a minus sign. (As in the equation a-b=c which we road in the following way: a minus b is equal to c).

The sign x (cross) stands for multiply. It is multiplication sign. (As in the equation 3x3=9 which we read 3 by 3 equals 9).

The sign: means to divide. It is a division sign. (As in the equation. 3: 3=1, that is 3 by 3 is 1).

Task 2. Retell the text.

X. Read the following information and ask your partner questions "Do you know...?"

It is interesting to know that

... the oldest University in the world is the Egyptian University.

... Oxford is the oldest University in England.

... Cambridge University is one of the biggest and oldest universities in England. They built it in the 13th century. It trains about 14,000 students.

... the earliest houses in Britain were round. They were built of wood.

... London's first underground railway of the "tube" type was opened in 1863.

Unit 5.

Grammar: The Participle.

Pre-text Exercises

I. Practise reading of the following words:

Electricity [ılek’trısıtı], motor [’m∂ut∂], temperature [’temp-rıt∫∂], either [’aıð∂], thousand [’Θaus∂nd], continuous [k∂n-’tıgju∂s], numerous [’nju:m∂r∂s], foreign [’f rın], contribute [k∂n’trıbju(:)t], development [dı’vel∂pm∂nt], result [rı’zΛlt], vacuum [’vækju∂m], machine [m∂’∫i:n], familiar [f∂’mılj∂], night [naıt], bicycle [’baısıkl], mechanical [mı’kænık∂l], object [’ bd z ıkt], pyrometer [paı’r mıt∂], imagine [ı’mæ-d z ın], civilization [,sıvılaı’zeı∫∂n], refrigerator [rı’frıd z ∂-reıt∂], weigh [weı], telephone [’telıf∂un].

II. Try to memorize English words and word-groups and their Ukrainian equivalents:

application - застосування, as for - що стосується, current - струм, device - прилад, to do without - обходитися без, furnace - піч, inventor - винахідник, laboratory - лаборатория, to make use of - застосовувати, to measure - вимірювати, to play a part - відігравати роль, scientist - учений, to serve - служити, to transform - перетворювати, to weigh - важити.

III. Translate the words and their derivatives into Ukrainian:

application - to apply - appliance - applicable; electrical -electricity - electrically - electrician; inventor - invention - to invent - inventiveness; to measure - measure - measurement -measurable; science - scientist - scientific - scientifically; to serve - service; to transform- transformer - transformation; to weigh - weight - weightless - weightlessness.

IV. Translate the following sentences:

1. The student is translating an article on refrigerators.

2. The student has translated an article.

3. The article is translated by the student.

II. Form sentences according to the model using the verbs given below.

Model: We can't help + Gerund...... ®We can't help speaking about the achievements of modern medical science.

to answer, to repeat, to mention, to observe, to change, to think, to remember.

III. Fill in the blanks with the words ONE or FOR.

1. Moscow is...of the largest cities in the world. 2.... must remember that it is necessary to study English at least an hour a day. 3. As... rubber it was brought to Europe as early as the 15th century. 4....understands the importance of electricity when... sees trams, trolley-buses and trains driven by it. 5. The energy of the atom is used... peaceful purposes in our country. 6.... must know the chemical properties of the atom. 7. We produce rubber... it is quite necessary... the development of our industry. 8. In 1819 Volta returned to Come... he wanted to spend the rest of his life there. 9. This is a more important problem than that.... 10. I haven't got a dictionary, I must have....

IV. Translate the following sentences paying attention to the infinitive.

1. This is the device to be used in our experiment. 2. The thermometer is a device to measure the temperature. 3. Where are the articles to be translated by the students? 4. The letter to be answered was given to me. 5. The generator is a device to change mechanical energy into electric energy. 6. The Soviet Union was the first to use atomic energy for peaceful purposes. 7. V. V. Petrov was the first scientist to study the electrification of metals by rubbing them. 8. I was the last to answer the teacher's questions.

V. Translate the following sentences using the infinitive:

1. To obtain the constant current one must have its source. 2. The pyrometer is used to measure the temperature of hot metals. 3. The man learnt to split atoms to get great amounts of

current was Volta after whom the unit of electric pressure, the volt, was named? His discovery developed out of Galvani's experiments with the frog, Galvani observed that the legs of a dead frog jumped as a result of an electric charge. He tried his experiment several times and every time he obtained the same result. He thought that electricity was generated within the leg itself.

Volta began to carry on similar experiments and soon found that the electric source was not within the frog's leg but was the result of the contact of both dissimilar metals used during his observations. However, to carry on such experiments was not an easy thing to do. He spent the next few years trying to invent a source of continuous current. To increase the effect obtained with one pair of metals, Volta increased the number of these pairs. Thus the voltaic pile consisted of a copper layer and a layer of zinc placed one above another with a layer of flannel moistened in salt water between them. A wire was connected to the first disc of copper and to the last disc of zinc,

The year 1800 is a date to be remembered: for the first time in the world's history a continuous current was generated.

Volta's Short Biography. Volta was born in Como, Italy, on February 18, 1745. For some years he was a teacher of physics in his home town. Later on he became professor of natural sciences at the University of Pavia. After his famous discovery he travelled in many countries, among them France, Germany and England. He was invited to Paris to deliver lectures on the newly discovered chemical source of continuous current. In 1819 he returned to Como where he spent the rest of his life. Volta died at the age of 82.

Exercises

I. For the words given in (a) find the Ukrainian equivalents in (b).

a) 1. instrument; 2. liquid; 3. means; 4. mercury; 5. purpose; 6. difference; 7. law; 8. matter; 9. heat; 10. light; 11. opposite; 12. condition; 13. flow; 14. behaviour; 15. charge;

b) 1. різниця; 2. peчoвинa; З. стан, умова; 4. зapяд; 5. потік; 6. piдинa; 7. ртутъ; 8. протилежний; 9. закон; 10. засіб; 11. теплота; 12. мета; 13. поведінка; 14. прилад; 15. світло.

4. The article is being translated by the student

5. The student translating the article is comrade Novikov.

6. The article translated by the student is difficult.

7. The translated article is devoted to electrical furnaces.

8. Translating the article, the student used a dictionary.

9. Having translated the article, the student gave it to the teacher.

10. Having been asked to translate the article, the student translated it with great interest.

11. The article being translated is about the application or electricity.

TEXT 5. ELECTRIC CURRENT AND ITS APPLICATION

The electric current was born in the year 1800 when Volta constructed the first source of continuous current. Since that time numerous scientists and inventors, Russian and foreign, have greatly contributed to its development and practical application.

As a result, we cannot imagine modern civilization without the electric current. We can't imagine how people could do without electric lamps, without vacuum cleaners, refrigerators, washing machines and other electrically operated devices that are widely used today. In fact, telephones, lifts, electric trams and trains, radio and television have been made possible only owing to the electric current.

The student reading this article is certainly familiar with the important part which the electric current plays in everyday life. From the moment when he gets up in the morning until he goes to bed at night, he widely uses electric energy. Only when going to the institute either on foot or by bicycle, can he do without electricity. In fact, it is well known that electric current is necessary for the operation of trolley-buses, trams, buses and modern trains.

During the day the student will also use some electrical devices working in the laboratory, making use of the telephone, the lift, the tram and so on. As for the evening, if he studies or reads by an electric lamp, watches television, goes to the theatre or cinema, he certainly uses electricity.

Some people are more familiar with the various applications of the electric current in their everyday life than they are with its numerous industrial applications. However, electric energy finds its most important use in industry. Take, for example

the electric motor transforming electric energy into mechanical energy. It finds wide application of every mill and factory. As for the electric crane, it can easily lift objects weighing hundreds of tons.

A good example, which is illustrating an important industrial use of the electric current is the electrically heated furnace. Great masses of metal melted in such furnace flow like water. Speaking of the melted metals, we might mention one more device using electricity, that is the electric pyrometer. The temperature of hot flowing metals can be easily measured owing to the electric pyrometer.

These are only some of the various industrial applications of the electric current serving us in a thousand ways.

Exercises

I. Answer the following questions.

1. When did Volta construct the first source of continuous current?

2. We can't imagine modern civilization without the electric current, can we?

3. What part does the electric current play in every day life?

4. What can you say about various applications of the electric current in everyday life?

5. How is the electric current used in industry? 6. What is the electric pyrometer?

II. Ask your partner questions using the information of the following sentences:

1. Since that time numerous scientists have greatly contributed to the development and practical application of the electric current.

2. The student in certainly familiar with the important part which the electric current plays in everyday life.

3. Electric energy finds its most important use in Industry.

4. The electric motor transforming electric energy into mechanical finds wide application at every mill and factory.

5. The electrically heated furnace is a good example illustrating an important industrial use of the electric current.

a) simultaneousness of action; b) priority of action.

Translate them into Ukrainian.

1. We shall translate this article 2. Do you know this man? 3. They can translate this text without a dictionary. 4. To translate this article is not an easy thing to do. 5. We want to translate this article. 6. I remember to have seen this man last year. 7. To study much is to learn much. 8. To master a language one must work much. 9. The professor to deliver a lecture at our institute is an outstanding scientist. 10. The experiment to be carried on is described in this article. 11. Can this work have been done in such a short time? 12. He must be reading a newspaper in the reading-room. 13. He was glad to have been travelling to Europe.

Text 11. From the History of Electricity

There are two types of electricity, namely, electricity at rest or in a static condition and electricity in motion, that is the electric current. Both of them are made up of electric charges, static charges being at rest, while electric current flows and does work. Thus, they differ in their ability to serve mankind as well as in their behaviour.

Let us first turn our attention to static electricity. For a long time it was the only electrical phenomenon to be observed by man. As previously mentioned at least 2,500 years ago, or so, the Greeks know how to get electricity by rubbing substances. However, the electricity to be obtained by rubbing objects cannot be used to light lamps, to boil water, to run electric trains, and so on. It is usually very high in voltage and difficult to control, besides it discharges in no time.

As early as 1753, Franklin made an important contribution to the science of electricity. He was the first to prove that unlike charges are produced due to rubbing dissimilar objects. To show that the charges are unlike and opposite, he decided to call the charge on the rubber - negative and that on the glass - positive.

In this connection one might remember the Russian academician V. V. Petrov. He was the first to carry on experiments and observations on the electrification of metals by rubbing them one against another. As a result he was the first scientist in the world who solved that problem.

Who does not know that the first man to get the electric

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