- •Vocabulary 138
- •Electric current serves lis in a thousand ways
- •Exercises
- •Active Words and Expressions
- •Exercises
- •Exercises
- •Lightning
- •Active Words and Expressions
- •Exercises
- •Magnetism
- •Exercises
- •Idioms early history
- •Active Words and Expressions
- •Exercises
- •Lomonosov
- •Active Words and Expressions
- •Exercises
- •Volta's short biography
- •Electric current
- •Active Words and Expressions
- •What is heat?
- •Active Words and Expressions
- •Electric circuit
- •Voltmeter
- •Conductors and insulators
- •Active Words and Expressions
- •Exercises
- •Insulator surface treatment
- •Electromotive force and resistance
- •Active Words and Expressions
- •Exercises
- •Heating effect of an electric current
- •Active Words and Expressions
- •Exercises
- •III. Complete the following sentences:
- •IV. Answer the following questions:
- •V. Translate the following word combinations:
- •VI. Define the meaning of the prefixes in the following words, translate them:
- •IX. Translate tfie following sentences paying attention to the words in bold type:
- •X. Read and retell the following text.
- •If there were no electricity
- •XI. Speak on the heating effect of an electric current.
- •IV. Translate the following sentences and define the functions of tfie word that
- •V. Translate the following sentences paying attention to the words in bold type:
- •VI. Fill in the blanks with suitable prepositions and form sentences with the following infinitives: -
- •VII. Compare:
- •VIII. Translate the following sentences, paying atten- tion to the words in bold type:
- •IX. Form nouns from the following verbs and translate them:
- •X. Give a short summary of the text.
- •XI. Look at Fig. 9 and describe Oersted's discovery.
- •XII. Describe fig. 10.
- •VI. Read the following abbreviations:
- •VII. Define the following terms:
- •IX. Form five sentences combining suitable parts of the sentence given in columns I and II:
- •II. Answer the following questions:
- •IV. Define the following terms:
- •V. (a) Choose the right term; (b) explain the statement:
- •VI. Translate the following sentences:
- •VII. Translate the following text:
- •VIII. Retell the text.
- •Transformers
- •3 Single-pnase transformers stepping generator voltage up to 275.000 volts
- •2300 To 230 volt
- •2300 Volt motor
- •230 Volt induction motor
- •Transmission system
- •IV. Form as many words as possible using suffixes and prefixes. Define what parts of speech the new words are and translate them:
- •V. Form nouns from the following words using suitable suffixes:
- •VI. Translate the following word combinations:
- •VII. Arrange the following words and expressions in pairs of a) synonyms, b) antonyms:
- •IX. Compare:
- •X. Translate the following text:
- •XI. Retell the text
- •IV. Translate the following sentences using the Passive Voice:
- •V. Form sentences according to the models given below:
- •VI. Answer the following questions:
- •IV. Answer the following questions:
- •V. Define the following terms:
- •VI. Form six sentences using the following nouns quali- fied by adjectives:
- •VII. Translate the following text:
- •VIII. Describe Fig. 15.
- •IV. Translate the following sentences:
- •V. Translate the following sentences:
- •VII. Give a heading to each paragraph of the text. Explain why you have given such a heading.
- •VIII. Speak on:
- •IX. Translate the following text:
- •Active Words and Expressions
- •Exercises
- •IV. Translate the following words and word-combinations:
- •V. Answer the following questions:
- •VIII. Speak on the possible uses of solar energy.
- •IX. Read and retell the following story;
- •1. Energy
- •2. Electric fish
- •4. Surface tension
- •5. Electric meter
- •7. Refrigerator
- •10. Electron theory
- •11. Thermocouple and photocell
- •12. Electric lamp
- •13. Faraday's discovery
- •15. Steam turbine
- •16. Units of measurement
- •17. Plasma generator
- •18. Laser
- •19. Semiconductors
- •20. Steam power station
- •21. Hydroelectric power station
- •22. Current flow
- •23. Gases, solids, liquids and plasma
- •Idioms, Conjunctional and Prepositional Phrases
- •Vocabulary
- •Impulse wheel ['impals ,wi:l] активная турбина
IV. Translate the following sentences using the Passive Voice:
1. Завтра будут получены приборы. 2. Студентам дали новые инструкции. 3. Об этих достижениях много говорят. 4. Меня просили провести испытание. 5. Пример последовал за правилом. 6. Нам показали новые материалы. 7. Их учат иностранным языкам. 8. Вчера ответили на эти письма.
V. Form sentences according to the models given below:
A.
Model: ... the research work to be finished ...
I told you about the research work to be finished in time
m 89
« • •
... the problem to be solved
... the temperature to be measured
... the story to be told ...
... quite necessary to transform ...
... too difficult to translate
ч
B.
V
Model: ... is expected to ...
The scientist is expected to deliver an interest ing lecture.
1.
2. 3. 4. 5. 6.
■ ■ •
VI. Answer the following questions:
1. What device is discussed in the present article? 2. What is a motor employed for? 3. What kind of motors do you know? 4. Does the generator convert electrical energy into mechanical energy? 5. What parts of a motor do you know? 6. What is a very strong magnetic field needed for? 7. What does the shunt field winding provide? 8. What does a motor do in our homes? 9. Do motors serve you every day? 10. Where does a motor find its wide application?
VII. (a) Form verbs using the suffix -ize:
civil, revolution, equal, neutral
Form verbs using the prefix over-: load, throw, grow, come, estimate, power, take
Form nouns using suffixes -or, -er:
work, translate, act, speak, steam, boil, conduct, engine, fact, heat
VIII. Translate the sentences and define the function of the word one:
1. One hundred years ago there were neither electric lamps, nor electric motors. 2. One might mention many more well-known facts and names. 3. The motor in question is more powerful than the one you spoke about yesterday. 4. There was only one problem to be solved. 5. The first student gave more correct answers than the last one. 6. One can reduce heat losses in a transmission line. 7. One of you will compare the results obtained.
IX. Fill in the tytanks with the following expressions:
to find application (in); to make use (of); to play an important part (in); to take interest (in); to pay attention (to).
1. Many Russian scientists of the past ... the development of Russian science. 2. Lornonosov ... not only in physics but also in chemistry. 3. We ... minute motors as well as mighty giants. 4. Insulators as well as conductors ... electrical engineering. 5. In the Soviet Union great ... the peaceful uses of atomic energy.
X. Complete the following sentences:
1. A transformer is a device which ... 2. A dynamo is a machine which ... 3. A battary is a device which ... 4. A switch is a device which ... 5. An engine is a machine which ... 6. A thermometer is a device, which ... 7. A motor is a device which ... 8. A generator is a machine which ...
XI. Describe Fig. 14.
XII. Speak on:
The use of electric motors in industry.
The use of electric motors in everyday life.
XIII. Translate the following text:
UNDERGROUND HYDROELECTRIC POWER STATION
In about 1889 what may have been the world's first underground hydroelectric power station was installed in one of the mines in America. This plant comprised six 40 in. impulse wheels operating under a vertical head of 1,680 ft, each runner being connected to a generator supplying power to the mill a short distance away. Designs and techniques have gradually improved during the past years and there are now 300 underground hydroelectric power stations either in service or under construction.
LESSON TWENTY-TWO
STATES OF MATTER
Among the most important effects of heat is that of changing the state of matter from a solid to a liquid, from a liquid to a gas, from a gas to a plasma. In effect, some substances are capable of existing in each of -the four possible states under suitable conditions of temperature and pressure. It is obvious that the process under consideration also depends on the quality of the Substance as will as on its volume. To effect a change of state under ordinary atmospheric pressure, it is necessary either to add or to remove a certain definite quantity of heat/On adding heat, one may expect a solid to change into a liquid, and the latter is turned into a gas. In some cases a solid body may change directly into a gas. Gas, in its turn, may be heated to a plasma state.
We generally find that each substance exists mainly in one given state. Iron, for instance, is usually thought of as a solid body, water as a liquid, and air as a gas.1 Nevertheless, we are also familiar with the transformation of the same kind of matter from its usual state to another and that transformation is effected by supplying or decreasing heat. For example, we know7 water to exist in three possible states, namely: as solid ice which can melt to form the liquid that we call "water", water in its turn evaporates to form a gas, that is to say, first vapour and then steam, when heated to the boiling point. The student is unlikely to distinguish between the English terms "steam" and "vapour". As long as there is still some water left unevaporated in the container, the steam formed will not be pure steam but will have some particles of water in suspension. Such steam is said to be wet steam and one may classify it as a vapour.
If we take a certain quantity of ice below the freezing point, that is below 0°C, and gradually heat it at a uniform rate, the temperature may be observed to rise steadily until the freezing point is reached. At this point the temperature stops rising and remains unchangeable while melting takes place. A considerable amount of heat is absorbed in order to effect the change of state from solid ice to water, while the temperature remains steady. This heat is said to be latent.
The ice having melted, the water again rises steadily in temperature until it begins to boil, turning rapidly into steam or water-gas. Then, again there is no rise in temperature and an even larger amount of "latent heat" is required but to effect the transformation from water to steam, without rise of temperature. Besides this rapid change at boiling, one may observe as well a gradual change into steam, even at ordinary temperatures. The process in question takes place on the surface when water is in an open container, or any other open place. It follows that in the open there will be a constant loss from the surface of the liquid and this loss will increase as the temperature rises. The above phenomenon is known as evaporation.
Fig. 15 illustrates water evaporating from an open container. The black dots represent greatly enlarged water molecules, the circles representing air molecules, also enlarged. The small arrows indicate that both air and water molecules are in a continuous motion. It is only the rapidly-moving molecules which are able to leave the surface of the liquid. Therefore, the mean velocity of those left behind will be decreased and the liquid will be cooled.
Active Words and Expressions
to absorb, container, to effect, evaporation, in suspension, latent heat, mean, pure, rapid, solid, state, surface, vapour, volume, wet steam
Exercises
/. Translate the following sentences paying attention to the participle:
1. Many substances can exist in more than one of the four possible states, that state depending on the substance itself as well as on its volume, temperature, and pressure. 2. Adding heat we change a solid into a liquid, the latter being changed into a gas. 3. Efficiency may be defined as output divided by input. 4. There is always water vapour in the air, the amount depending upon various conditions. 5. The resistance having been very high, the current in the circuit was low. 6. Steam is a gas into which boiling water changes, vapour consisting of the pure gaseous state together with particles of the liquid in suspension. 7. The flow of the current being reduced, the speed of the motor is decreased.
//. Translate the j:oI lowing sentences and define the function of the gerund:
1. The ampere is the electric unit used for measuring the electric current. 2. When the boiling point is reached, water temperature stops increasing. 3. Boiling takes place when the temperature of water reaches 100°C. 3. It is possible to add a considerable quantity of heat without changing the temperature of a given substance. 4. Various liquids have different boiling points. 5. Melting this metal will not take much time. 6. Even a schoolboy knows of the ohm being the practical unit of resistance. 7. One cannot study the early steps of atmospheric electricity without mentioning professor Rihman who constructed the first electrical measuring instrument. 8. The student certainly remembers Volta's having constructed the first source of continuous current. 9. When water reaches 100°C, it starts boiling, in other words, the process of boiling begins.
///. Find the поп-finite forms of the verb in the text and define their functions.