Прочитайте следующие предложения, выбрав подходящее по смыслу причастие I или причастие II, предлагаемое в скобках.

1. Newton assumed that light was made up of many small particles (moving I moved} at high speeds. 2. This figure represents light parti­cles (leaving I left) a source in many directions. 3. A group of such particles (travelling I travelled) parallel paths is called a beam of light. 4. The experiments (carrying I carried) out at our laboratory are rath­er interesting. 5. The metal (using I used) in that experiment was tita­nium. 6. The results (receiving I received) changed with the material used. 7. The problem (concerning I concerned) must be considered in detail 8. The period (following /followed) this invention was very productive.

Переведите следующие предложения на русский язык, обращая внимание на перевод причастия II с наречиями.

So far

So thus

так, таким образом

Thus far

до сих пор

1. The values thus found are of some interest. 2. The results so far received are not accurate enough. 3. The problem so explained was easily understood. 4. The articles thus far written on the subject are of no interest. 5. The work so done provided us with new data. 6. The method thus far used by us was effective enough. 7. The results thus achieved were of great help. 8. The measurements so far made are to be repeated.

Переведите предложения на русский язык, обращая внимание на независимый причастный оборот.

1. This is a device used for detection and measurement of light, its principle of action being simple. 2. The operation principle is based upon photoelectric effect, the latter arising as a result of energy transfer from light incident on a substance to electrons. 3. The device consists of two electrodes, one of them being coated with photoemissive material. 4. The material most often used for coating the cathode is caesium silver (цезиевое серебро), the latter being particularly sensitive to the red end of the spectrum. 5. The anode being maintained at a positive potential with respect to the cathode, the electrons are attracted to it. 6. The electric current passing through the device, we can measure light intensity incident on the cathode.

Переведите на английский язык.

1. Рассматриваемый прибор очень важен для проведения данного опыта. 2. Ученые, придерживающиеся этого метода, считают его впол­не удовлетворительным. 3. Данные, о которых идет речь, позволяют нам сделать несколько предположений. 4. Поведение данного веще­ства в этом эксперименте подтверждает нашу гипотезу (hypothesis). 5. Группа, выполняющая это задание (task), работает успешно. 6. Ис­точники света, называемые точечными источниками, имеют малый размер по сравнению с площадью, которую они освещают.

(6) Enjoy Yourself

PROFESSOR: If you were in Africa and saw a lion coming, what steps would you take? STUDENT: The longest steps I could.

lion n — лев; step n — шаг; to take steps — принимать меры

UNIT 36 (1) Grammar

ГЕРУНДИЙ (GERUND)

Герундий — неличная форма глагола, совмещающая в себе свойства глагола и существительного и дающая отвлеченное поня­тие о действии, не указывая на лицо, число и наклонение.

На русский язык герундий переводится именем существительным, неопределенной формой глагола, деепричастием или целым пред­ложением.

Герундий в синтаксической функции обстоятельства всегда упот­ребляется с предлогами in, on, upon, after, with(out), by и др. Сле­дует обратить внимание на смысловое значение предлогов in и on.

The branch of electronics dealing with the emission of electrons from substances under the action of heat, particularly the study and design of thermionic valves of tubes, is called thermionics.

A good high vacuum is practically a perfect nonconductor, since in it no carriers of electricity are present. If two metal plates or electrodes are enclosed in a vacuum by a glass tube, we have an open circuit and no current will flow. However, one of the electrodes being heated to a high temperature, the thermal velocity of some of the conduction electrons in the metal becomes high enough for these electrons to escape. In moving through a vacuum these electrons form an electric current.

The effect of thermionic emission is due to the fact that some of the free electrons in metal under certain conditions can obtain such a ve­locity, that their kinetic energy is great enough to overcome the molec­ular forces of attraction and so they may leave the metal surface. The mean velocity of the electrons in the metallic conductor is not high enough to cause more than a very small percentage of the electrons to be ejected.

Nevertheless, the electrons leaving the metal surface can produce con­siderable currents. Electrons can as well escape from cold metal surfaces in case they are acted upon by so high an electric field (approximately 10⁷ volt/cm or more), that the molecular forces of attraction are over­come by it.

A thermionic valve is a system of electrodes arranged in an evacuated glass or metal tube. For special purposes a gas at low pressure may be introduced into the valve. The heated electrode is called the cathode (or sometimes the filament) and the cold electrode — the plate. The cathode is an electrode which is held at a negative potential with respect to the plate. It emits electrons. The cathode of a tube may be in the form of a wire which is heated or it may be a metal tube coated ^vith certain metal­lic oxides, which is heated by a separate heater. In the former case the cathode is known as " filament", in the latter, it is called an " indirectly heated cathode". In both cases the heating of a substance causes it to emit electrons. The device is called a diode and if we apply an alternat­ing current to a vacuum tube it behaves as a one-way resistance, elec­trons flowing from cathode to plate but not from plate to cathode.

With polarity reversed, there can be no current of electrons at all. Sup­pose an a-c voltage is applied to terminal A. During each positive cycle current will flow through the diode and the voltage drop across the re­sistance R will be the value of the diode current times R. Note, that al­though the voltage of A is negative 50 percent of the time, the voltage of В is never negative. The voltage of В can be used to charge up a capaci­tor. This application of the diode called a diode rectifier can convert an

fcJ-ЧР—

!

 

a-c voltage into d-c voltage, all a-c operated radio and TV sets having diode rectifiers to convert the alternating current into direct current.

The vacuum tube was invented in 1904 by Sir John Ambrose Fleming, a British electrical engineer. It was the heart of the electronic circuit until 1947. For 40 years this device underwent constant improving and by 1947 it had come in so many different shapes and sizes and had per­formed so many different functions, that it seemed absurd to suppose it could ever be replaced.

ЗАДАНИЯ К ТЕКСТУ

• Выпишите из текста английские эквиваленты следующих русских словосочетаний:

под воздействием; носители электричества; тепловая скорость; электроны проводимости; в определенных условиях; молекулярные силы притяжения; ток диода; недостаточно высока, чтобы вызвать; в случае, если на него воздействует; если применить (подать) пере­менный ток; одностороннее сопротивление; диодный выпрямитель

• Употребите подходящие по смыслу слова из предлагаемых в скоб­ках вариантов.

1. In a perfect nonconductor (some I no) carriers of electricity are present. 2. Current (will I will not) flow in an open circuit. 3. The mean velocity of the electrons in the metallic conductor (is I is not) high enough to cause great percentage of the electrons to be ejected. 4. The electrons leaving the metal surface (can I can't) produce considerable currents. 5. Electrons can escape from (hot I cold I hot and cold) metal surfaces. 6. Electrons can escape from cold metal surfaces in case they are acted upon by high (temper­ature I electric field). 7. If the kinetic energy of an electron is not great enough to overcome the molecular forces of attraction it (can I can *i) escape from the metal surface. 8. The heated electrode in a diode is called the (filament I plate). 9. A diode behaves as a one-way resistance if we apply a(n) (alternating I direct) current to it. 10. The (filament I plate) collects electrons which (the plate I the filament) emits.

• Заполните пропуски в предложениях подходящими по смыслу сло­вами.

1. Thermionics is a branch of electronics dealing with the... of.... 2. In a nonconductor no... of electricity are present. 3. No current will flow in an open.... 4. The electrons escaping the metal surface form an electric.... 5. When metal is heated, the kinetic energy of some of the electrons becomes high enough to... the molecular forces of.... 6. If we apply an alternating current to a diode, it behaves as a one-way.... 7. A diode... can convert an a-c voltage into d-c voltage.

 

Reading 36B

Прочитайте текст и скажите, чем отличаются данные электроваку­умные приборы от диода и для каких целей они применяются.

When the third electrode, called the grid is placed in the circuit be­tween the cathode and the plate, the tube is known as a triode. *The purpose of the grid is to control the flow of plate current.

When the tube is used as an amplifier a negative d-c voltage is usually applied to the grid. Under this condition the grid does not draw appreci­able current. The number of electrons attracted to the plate depends on the combined effect of the grid and plate polarities. *Hence, when the voltage on the grid is varied in accordance with the signal, the plate cur­rent varies with the signal. *A small voltage applied to the grid can con­trol a comparatively large amount of plate current and the signal is am­plified by the tube. The grid, plate, and cathode of a triode form an elec­trostatic system, each electrode acting as one plate of a small condenser. *The capacitances are those existing between grid and plate, plate and cathode, and grid and cathode. These capacitances are known as inter-electrode capacitance.

*The effect of undesired coupling between the input and output circuit in a triode can be avoided by placing an additional electrode called the screen into the tube and thus reducing the capacitance between the grid and the plate. With the addition of the screen the tube has four electrodes and is accordingly called a tetrode. The screen is placed between the grid and the plate, and acts as an electrostatic shield between them, thus re­ducing the grid-to-plate capacitance.

Pentode is a tube with five electrodes: anode, cathode and three grid-type electrodes. The grid nearest the cathode is the control grid, the next is the screen grid and that nearest the anode is a suppressor grid. *The suppressor grid repels secondary electrons and prevents bombardment of the screen grid by them.

• Объясните, как вы понимаете выделенные в тексте слова.

• Переведите на русский язык предложения, помеченные звездочкой.

(4) Conversation Practice

•Answer the questions on Texts 36A and 36B.

1. What does thermionics deal with? 2. Why is a good high vacuum a perfect nonconductor? 3. What do we call an open circuit? 4. What must we do to start thermionic emission? 5. What is the effect of thermionic emission due to? 6. On what condition can electrons escape from cold surfaces? 7. What is diode? 8, How many electrodes are there in a diode?

9. What is the heated electrode called? 10. What is the cold electrode called? 11. In what case does a diode behave as a one-way resistance? 12. What way do electrons flow in a diode? 13. Where and what purpose are diode rectifiers used for? 14. What is a triode? 15. How many electrodes are there in a triode? 16. What are these electrodes called? 17. Where is the grid placed? 18. What purpose is it placed for? 19. What does the grid control? 20. What are triodes used for?

• Describe the arrangement of valves using the scheme before Text 36A.

• Speak on the following topics:

1. Electronics, its object of study and the fields of application.

2. The physics of thermionic emission.

3. Design of vacuum tubes and their application.

4. The principle of the rectification action.

5. The inventor of a vacuum tube and the lifetime of his invention.

(5) Home Exercises

1. Образуйте производные формы следующих глаголов:

to charge - - заряд, заряженный, заряжающий, заряжая, зарядив, незаряженный

to reflect — отражение, отражающий, отражая, отразив, неотра­женный

to rectify — выпрямитель, выпрямляющий, выпрямляя, выпрямив, невыпрямленный

to suppose — предположение, предполагающий, предполагая, предположив

2. В следующих предложениях найдите герундиальные или причаст­ные конструкции, установите их функцию и переведите предложения на русский язык.

1. I never doubted his working in this field of science. 2. Scientists' constantly exploring the unknown, their looking for new knowledge and the answers to unsolved questions cannot be overestimated (переоценить). 3. One must not forget that there are plenty of problems remaining still unsolved. 4. Using their minds and working together men can solve almost any problem. 5. Scientists' working together and their sharing ideas with one another is of great advantage for science. 6. Even when working alone a scientist must know what others have done before him. 7. Being pioneers scientists go ahead preparing the way for those following them.

3. Напишите вопросы к выделенным членам предложения.

1. The electrons leaving the metal surface can produce considerable current. 2. The escaping electrons flow from the cathode to the plate.

3. The number of electrons attracted to the plate depends on the combined effect of the grid and plate polarities. 4. A triode contains three electrodes. 5. Electron tubes are widely in use nowadays. 6. One must use special instruments while carrying out this experiment.

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1. A. законом, иными правовыми актами или договором.
2. Gerund переводится на русский язык существительным, деепричастием, инфинитивом или целым предложением.
3. I. Драма одаренного ребенка, или как становятся психотерапевтами.
4. I. О СЛОВЕ БОЖИЕМ, ИЛИ СВЯЩЕННОМ ПИСАНИИ
5. I.Закончите предложения, употребляя сложное дополнение.
6. II Д.Г. ЛОУРЕНС, ИЛИ ФАЛЛИЧЕСКАЯ ГОРДОСТЬ
7. II. Найдите фрагменты из британских или американских видеофильмов,
8. III. Определите значимость для переводчика изучения особенностей литературного направления, к которому относится тот или иной автор.
9. III. Переведите следующие предложения и определите тип интернационализма.
10. IV ФИЗИЧЕСКАЯ РЕАБИЛИТАЦИЯ ПРИ ЗАБОЛЕВАНИЯХ ОРГАНОВ ДЫХАНИЯ
11. IV. В следующих предложениях подчеркните модальный глагол или его эквивалент. Переведите предложения на русский язык.
12. IV. Переведите глаголы, пользуясь словарем. Поставьте вместо точек подходящий по смыслу глагол. Предложения переведите.