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Grammar: Ing forms: Participle/Gerund/Verbal Noun


I.           Practice reading the following

one-syllable words:

end, small, help, set, done, well, heat, field, gold

two-syllable words with the stress on the first syllable:

latter, mainly, tiny, laser, complex, copper, other

two-syllable words with the stress on the second syllable:

device, supply, design, direct, extreme, inside, rely, occur


electrical engineering, intermediate place, thermal elements, vacuum tubes, extremely sensitive, radioactive radiation, photoelectric properties, engineering purposes, cadmium sulphide, measuring instruments

words with double stress:

extraordinary, outstanding, engineering, radioactive, radiological, opto-electronics

II.        Memorize the spelling and pronunciation of the following words

Electronics lek trOn ks] 

Optoelectronics  [Optq lek trOn ks]

Engineering [ endZ n qr техніка

Technology [tek nOlqdZ технологія

Economical [ i kq nOm kql економічний

Transistor [tr n z st q транзистор

Element ['el mqnt компонент

Compound ['kOmpaund з’єднання

Crystal ['kr stl кристал

Instrument [' nstrumqnt прилад



Ever since electrical engineering and, later on, radio engineering, came into being, and up to the end of the first half of the 20-th century, metals and dielectrics were mainly used. They were very good or very poor electricity conductors. Semiconductors occupy an intermediate place between metals and insulators.

Transistors made it possible to design compact, small-dimensioned electronic devices, which consume very little power. The transistors are successfully used for direct transformation of heat energy into electrical energy by means of thermal elements. They are also used to transform radiant energy into electricity with the help of photocells or so-called solar batteries. In later years light sources and lasers were built on the basis of transistors.

Transistors revolutionized radio engineering and electronics. Because of their small size, the absence of incandescence and other properties, transistors make it possible to produce devices which cannot be made with vacuum tubes.

Transistors are extremely sensitive to external influences. Even thousandths of one per cent of admixtures change their electrical conductive properties by hundreds of thousands of times. They are very sensitive to the action of light, nuclear particles, pressure, etc.

The turning of the tiny crystal into a transistor device, sometimes of extreme complexity, is achieved by adding mixtures to it. The outer looks of the crystal may not change when this is done, but alien atoms appear inside it, imparting new properties to the crystal.

Transistors are very sensitive to light, some of them react even to starlight. Cadmium sulphide as well as a number of other transistors, act as insulators in darkness. But already under ordinary room lighting their resistances decrease millions of times. This property was used as the basis for making the so-called photoresistances. Some of them react not only to visible light, but also to ultra-violet, infra-red and X-rays, and radioactive radiation. At present such photoresistances, being very small in size, are successfully used as the main elements for various measuring instruments and automatic devices.

The energy of light is transformed directly into electricity in photocells. It is precisely this energy that is used to power sputniks and spaceships with electricity. The photoelectric properties of transistors are largely used in TV sets, and other devices.

Opto-electronics holds out great promise. It is a synthesis of optics and electronics done on the basis of transistors. In this case electricity is directly transformed into light energy with great efficiency. Research in this field has already led to the making of miniaturized, reliable sources of light of very simple design. In the future they will be used on a great scale in computers, automatic devices, aviation, communications, etc.

The supply of transistors is inexhaustible. But up to now only a limited number of them are being used for engineering purposes. Semiconductors are – germanium, silicon, selenium and some of the simple compounds, like lead sulphide and arsenic and phosphoruses with indium and gallium. The electrical properties of germanium may be changed provided the latter is exposed to light. A very fine technology has been developed for obtaining transistors with pre-set physical properties by introducing into them admixtures of gold, copper, nickel, zinc, etc.

N o t e s


holds out great promise

pre-set –

Answer the questions:

1. What is a semiconductor? 2. What is a transistor? 3. What place do semiconductors occupy? 4. What are transistors successfully used for? 5. What kind of electronic devices is it possible to design with the help of a transistor? 6. With the help of what batteries are transistors used to transform radiant energy into electricity? 7. What is the size of transistors? 8. How do some transistors act in the dark? 9. Are photoresistances small or big in size? 10. Where are the photoelectric properties of transistors widely used? 11. In what case is electricity directly transformed into light energy with great efficiency? 12. Is it possible to make miniaturized reliable sources of light of very simple design or not? 13. Where will transistors be used on a large scale in the future? 14. Do you know any transistor devices?


I.           Translate the sentences paying attention to the conjunction both…and:

1. In later years both light sources and lasers were built on the basis of transistors. 2. Both silicon and germanium are semiconductors.  3. Transistors are very sensitive both to the action of light and to that of nuclear particles. 4. Both cadmium sulphide and number of other transistors act as insulators in darkness. 5. Some of the photoresistances react both to visible light and to radioactive radiation. 6. Such photoresistances are successfully used as the main elements both for various measuring instruments and automatic devices.

II.        Translate the following words and word-combinations:

Heat energy, radio engineering, transistor crystals, , vacuum tubes, light sources, future technology, room lighting, radioactive radiation, light-energy, engineering purposes, semiconductor devices, high voltage transmission lines, coal deposits, to power machines, to power spaceships with electricity, to occupy an intermediate place, to impart new properties, to impart knowledge, one per cent of admixtures, different admixtures, admixtures of some metals, to expand the range of transistors, to expand the use of crystals, to expand the application of new measuring instruments, in this case, in that case, in case, some of simple compounds, the same simple compounds, some tiny crystals, the same tiny crystals, the so-called solar batteries, the so-called photoresistances, because, because of, by means of, by no means, by all means

III.     Group the synonyms and translate them:

Demand v get v

Precisely adv receive v

Small-sized a decrease v

Obtain v aim n

Ordinarily adv exactly adv

Reduce v small-dimensioned a

Purpose n usually adv

require v

IV.     Group the antonyms and translate them:

Successful a outside adv

Visible a inner a

Like a impossible a

Directly adv inexhaustible a

Inside adv unreliable a

Possible a complex a

Increase v unlike a

Exhaustible a indirectly adv

Reliable a invisible a

Simple a decrease v

Outer a unsuccessful a

V.          Translate the words paying attention to the prefixes pre-, super-, in-, dis-:

prerevolutionary, prehistoric, pre-establish, prefabricated, predetermined, pre-set, precast, preheat, pre-sonic, superprecise, superconductor, superconductivity, super-high, inexhaustible, impossible, irregular, disadvantage, disconnect

VI.     Translate the sentences using either…or, bothand, as well as:

Напівпровідники використовуються як у фізиці, так і в техніці.

2. Метали та діелектрики є або дуже

Сульфід кадмію, як і інші транзистори, діють як ізолятори у темряві.

VII.          Translate the sentences paying attention to the meanings of “provided”:

1. These experiments provided data necessary for the completion of our research. 2. All the members of the expedition are provided with all the necessary things. 3. Provided our plant is equipped with up-to-date machinery, we’ll be able to raise the quality of the manufactured goods.

VIII.       Make up questions to the words in bold type:

1. Small dimensioned electronic devices consume very little power. 2. Under ordinary room lighting the resistance of transistors decreases millions of times. 3. Transistors revolutionized radioelectronics and electronics.

IX.     Fill in the blanks with the words given below:

Transformation, energy, properties, supply, insulators, sensitive, occupy, efficiency.

Semiconductors … an intermediate place between metals and insulators.

The transistors are successfully used for direct … of heat energy into electrical power.

Transistors are extremely … to external influences.

Cadmium sulphide as well as a number of other transistors, act as … in darkness.

The photoelectric … of transistors are largely used in TV sets, and other devices.

In this case electricity is directly transformed into light energy with great … .

The … of transistors is inexhaustible.

The … of light is transformed directly into electricity in photocells.

X.        Finish the sentences:

Semiconductors occupy …

The transistors are successfully used for …

Transistors are extremely …

Cadmium sulphide as well as …

The photoelectric properties of transistors …

The turning of the tiny crystal into a transistor device …

A very fine technology has been developed for…


Transistors and Semiconductor Devices

Study the text. Try to understand all details. Use a dictionary if necessary:

Devices consisting of solid pieces of crystalline material which allowed alternating current to flow more readily in one direction than the other were known long before the invention of the thermionic valve. The crystal set1 which became so well known in the early days of radio depended on the rectifying action at the point of contact between the surface of certain crystals and a fine wire. Crystal valves2, using silicon crystals, were found to be more efficient for the very high frequency signals reaching radar receivers than any thermionic valves. The action of these devices was not understood, but they were all made from materials which we now classify as semiconductors: substances which let electric current pass through them more easily than insulators do but much less easily than do true conductors.

In 1948 Bardeen and Brattain invented the point-contact transistor and Shockley invented the junction transistor shortly after. The transistor is a semiconductor triode possessing characteristics which are similar in many respects to those of thermionic triodes. At present transistors are widely used in amplifiers, receivers, transmitters, oscillators, TV sets, measuring instruments, pulse circuits, computers, and many other types of radio equipment.

The invention of transistors and solid-state devices led to an acceleration in the growth of electronics. Why were these new devices so important and why are they steadily replacing their older equivalents? A brief review of their advantages compared with thermionic devices will provide the answers to these questions. Transistors are made from parts which do not wear out. Transistors waste very little power. They require no heating to generate their free electrons. This means that equipment made with transistors is more efficient, lighter than comparable valve equipment.

Since no heating is required there is no delay in transistor equipment waiting for things to warm up, as there is with thermionic valves. This is a great advantage with ‘entertainment’ equipment, such as radio and television receivers, and it may be vital with some kinds of measuring or recording equipment.

Their very small size and weight, combined with low heat dissipation3, permits very high density packing of components and, in combination with their reliability, this has made possible the design of the very compact circuits which are essential for such applications as computers, portable measuring instruments, satellite instrumentation, etc.

No t e s

crystal set

crystal valve

heat dissipation –


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