1. Practise reading the following one-syllable words:

based, made; kind, wide, fine, device, light; main, way, space; wealth, beam, spread.

2. Practise reading the following two-syllable words:

labour, basic, laser, cutting, narrow, mankind; became, advance, define, affect, direct, invent, intense, liquid.

3. Practise reading the following many-syllable words:

   1. develop, efficient, productive, significant, possibil­ity, discovery;

   2. activity, technology, practical, character, industry, powerful, energy, explosion.

4. Read observing correct pronunciation of vowels in unstressed syllables:

practical, principal, maximum, spectrum.

5. Memorize the spelling and pronunciation of the following words:

intense [in'tens] — інтенсивний, quantum ['kwontsml — квант, thermal Г0э:тэ11—термічний, тепловий, equilib­rium [,i:kwi'libri9ml — рівновага, diameter [dai'aemitol — діаметр, mankind [masn'kaindl—людство, mobile — ['moubaill — рухомий, oscillate ['oisileitl — рухатися, віб­рувати.

6. Practise connected reading:

the century of lasers, miracle-making beam, the use of lasers, quite possible, making and concentrating light waves, increases the intensity, the laws of quantum mechan­ics, .elecromagnetic radiation energy, compressed in space, the most flexible and mobile element, highly pointed and powerful flux of energy.

TEXT A. LASER TECHNOLOGY

The next century may well become the century of lasers. This miracle-making beam is the symbol of the 20th cen­tury technology. There is no doubt that the use of lasers will be very widespread in the nearest future. Quite possibly, it will be as widely used as electronic devices are today.

What is laser? It is a device for making and concentra­ting light waves into a very intense beam. The letters LASER stand for Light Amplification by Stimulated Emis­sion of Radiation. The light made by a laser is much more intense than ordinary light. With ordinary light all the light waves are of different lengths. With lasers all the light waves are of the same length, and this increases the in­tensity.

The functioning of lasers is governed by the laws of quantum mechanics. The laser is a device in which energy (thermal, chemical or electric) is transformed into electro­magnetic radiation energy, a laser beam with maximally low entropy.

The quality of laser energy is determined by the pos­sibility of its high concentration both in space and in time. The laser beam is first compressed in time, i. e. transformed into a short pulse. Then it may be com­pressed in space focusing it to a fine point with a dia­meter of the order of a light wave length, thus obtain­ing energy density which, to date, evens that of a nuclear explosion. Laser energy can also be concentrated within a very narrow spectrum interval. This makes the laser a very fine instrument.

The world's first ruby laser had a dark-red beam. Other lasers were then produced, whose beam oscillated in crystals of a different composition, in semiconductors, gases, and liquids. And the beams were blue, green or invis­ible—infrared. What they have in common is that the beam is always space-bound and carries a highly pointed and powerful flux of energy.

Laser energy may be transformed practically without loss into many familiar forms of energy.

As each of new kinds of energy was mastered, "mankind gained new possibilities for its development. But discovery of the laser signifies something greater than simply mastering a new kind of energy. Wide laser application in production signifies a revolution in the implements of labour — the most flexible and mobile element of the productive forces.

VOCABULARY NOTES

1. fine point — надзвичайно гострий кінець

2. of the order of — порядку

3. to master smth.— оволодівати чим-небудь

4. implements of labour — знаряддя праці -

5. to have in common — мати щось спільне

6. flux of energy — потік енергії

7. highly pointed — з надзвичайно гострим кінцем

•

EXERCISES

1. Find In the text nouns formed after the models V + tion, V + ing (oscillate— oscillation, cut — cutting) and give their Ukrainian translation.

2. Translate into Ukrainian the following word-combinations:

   1. S + S construction: miracle-making beam, electron device, light waves, laser beam, energy density, ruby laser, laser application, quantum mechanics, radiation energy, production forces;

   2. A + S construction: fine instrument, flexible element, productive forces, thermal energy, electronic device.

3. Give English equivalents of the following words and ex­pressions:

цілком може стати, немає сумніву, найближче майбутнє, електронний прилад, звичайне світло, закони квантової механіки, якість, лазерний промінь, ентропія, визначати, отримувати, вузький інтервал, людство, знаряддя вироб­ництва, виробничі сили, коливатися, напівпровідник, рідина, відкриття.

4. Translate the following English words of the same root into Ukrainian, state the part of speech:

Model: light (світло) — to light (світити) — light (світ­лий)

state, research, device, fall, power, study, heat, form, stage, process, beam, layout.

/

5. Read the following text, write out words in bold type and translate the sentences into Ukrainian:

v «

LASER IN THE CLOTHES-MAKING INDUSTRY

Clothes-making factories have the following procedure for mass sewing of clothes. Thick stacks of cloth are put on a large layout table, and then each stack is cut out with knives which look like jig-saws to fit a pattern. This leads to a considerable waste of cloth. In the process of bringing parts of clothes to fitness rather wide strips of material are thrown out as refuse.

Now a practically waste-free technology seems to have been found for this operation An installation for laser lay­out of cloth designed at a Special Design and Development Bureau of the Clothes Manufacturing Industry has been built by the Shipyard in St. Petersburg.

In keeping with a set programme, a laser beam bums through a thick stack of cloth without shifting the layers (as it happens in cutting with knife) and it does not require making allowances "just in case".

6. Arrange the following words according to:

   1. similar meaning: basic, useful, modern, major, main, valuable, up-to-date, exact, principal, punctual, obtainable, high, great, available;

   2. opposite meaning; difficult, simple, outside, easy, complex, individual, inside, brief, collective, wide, long, narrow.

7. Translate into English using words and expressions from the text:

1. Лазерний промінь — це символ технології XX сто­ліття. 2. В найближчому майбутньому лазер буде так ши­роко використовуватись, як електронні прилади. 3. Світло лазера набагато інтенсивніше, ніж звичайне світло. 4. Ро­бота лазера відбувається за законами квантової механіки. 5. Лазерна енергія може перетворюватися практично без втрат. 6. Широке використання лазера у виробництві символізує революцію у знаряддях праці. 7. Найуживані­ші лазери — це геліо-неонові лазери. 8. Зараз лазери використовуються в багатьох виробничих, наукових і медичних цілях.

8. Put questions to the words in bold type:

The greatest success of lasers has been in drilling rubies in the watch-making industry. Lasers are also widely used in drilling the diamonds employed as dies for drawing wire. In the electronic industry they serve for drilling and cutting the ceramic substrates for integrated circuits and for trimming such circuits and discrete electronic components. The aero­space industry uses lasers for drilling holes in parts made of exceptionally hard materials.

9. Insert prepositions where necessary and translate into Ukrainian:

1. ... welding laser tools can operate ... two waysi ... conduction and ... deep penetration. 2. A laser beam put...

work ... cutting can easily be made fully automatic ... computerized numerical control. 3. Running ... a fully au­tomatic programme, a laser cutting tool can greatly im­prove precision, reliability, flexibility and productivity. 4. The flexibility ... the laser beam greatly facilitates auto­matic operation. 5. Laser welding is found ... electronics industry. 6. The absorption ... a quantum ... visible or ultraviolet radiation alters the state ... excitation ... the

electronic structure ... an atom or a molecule.

•

10. Find in the text sentences with:

    1. surbodinate clauses; explain their type;

    2. constructions "as ... as", "not so ... as".

11. Answer the following questions on the text:

1. What is a laser? 2. Where does the word "laser" come from? 3. What laws govern the functioning of lasers?

4. What is the quantity of laser energy determined by?

5. What makes the laser a very fine instrument? 6. Where does the laser find a wide application? 7. What types of lasers can we speak of?

   12. Using the text and the questions of ex. XI compose a dialogue and reproduce it.

TEXT B. HOW DOES A LASER WORK?

1. Pay attention to the pronunciation of the following words:

circle ['soikll — обертатися, крутитися, neon Гпі:зп] — неон, partial Cpa: Sol I — частковий, inefficient [_yini'fiSent] — неефективний, watt [wotI—ват, neodymium [^nirou'di- mioml — неодій, yttrium ('itrioml — ітрій, excited Iik'sai- tidl — збуджений, processing ['prousesigl — обробка, automobile [^toumou'biill — автомобіль, diversity [dai'- V9:sitil—різноманітність, available [o'veilobll— доступ­ний, наявний, plasma ['plaszmol — плазма.

2. Words and expressions necessary to comprehend the text:

to give off (energy) — виділяти (енергію), the right kind (of atoms) — відповідні (атоми), power supply — дже­рело живлення, solid-state laser — лазер твердотілий, out­side the field — що не стосується даної галузі, to be aware — усвідомлювати (знати), a model of (inefficiency) — зразок (неефективності),. to rack one's brains — ламати собі голову, in search for — в пошуках, scientists succeeded in obtaining — вченим вдалося (пощастило) отримати, inLESSON NINE

Grammar: 1.	Conjunctions Introducing Adverb­
	ial Clauses of Cause or Reason and
•	the Prepositions of Causal Rela­
	tions.
2.	The Infinitive (Forms and Func­
	tions).
3.	Review of Continuous Tenses (Ac­
	tive and Passive Voice).
4.	Word-building and Word-combina­
	tions.

READING EXERCISES