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Exercise 2. Answer the following questions.

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1. What does a thermometer tell us?

2. Does a thermometer tell you the amount of internal energy in a substance?

3. Why can the lake give up more energy than a cup of boiling water?

4. What does the amount of energy in a given body depend on?

5. What will happen to a piece of ice if it is placed in contract with heated metal ball?

6. Does the temperature of an object indicate the amount of energy contained in it?

7. Is heat transferred from a cold body to a hotter one?

8. What does the expression “the same temperature” mean?

 

Exercise 3. Give different Ukrainian meanings of the following words.

amount, point, indicate, depend, iron, mean.

 

Exercise 4. Form new words using prefixes and suffixes.

measure, internal, change, consider, boil, similar, quantity, heat, sufficient, transfer, important.

Exercise 5. Translate the following sentences paying attention to the words in bold type.

1. If the water is heated in a closed container, the temperature and the pressure both rise.

2. Both Lomonosov and his friend Rihman worked at atmospheric electricity. Both of them made experiments on that subject.

3. Take both a small cup of boiling water and a large container also full of boiling water; you will find that both of them have the same temperature.

4. “Work” is both a word used in everyday life and a scientific term.

5. Gases have neither size nor shape.

6. Neither of the two experiments was carried on successfully.

7. Heat was considered to be a weightless substance which was neither created nor destroyed.

8. Neither of the observed substances could be heated to a high temperature.

 

Exercise 6. Write out the keywords and phrases and make up a plan of the text.

Exercise 7. Make a short summary of the text (5-7 sentences).

 

Lesson 3.

Part A.

affect впливати
application застосування
attempt спроба
attention увага
average середній, середнє число
centigrade Цельсій
certainly звичайно
chamber камера
channel протока, канал
charge навантаження, заряд
collide зіткнутися
combustion згорання
conduct проводити
connect з’єднувати, сполучати
consequently отже, тому
constant постійний
convert перетворювати
dimension розміри, обсяг
due to завдяки
evident очевидний
exist існувати
expansion розширення
expend розширювати
fission розщеплення
force сила
freer замерзати
gaseous газоподібний
generation покоління
grade градус
helium гелій
hence віднині
inversely обернено
linear лінійний
liquid рідина
matter речовина
modern сучасний
observe спостерігати
obtain одержувати
perfect досконалий
plane площина
plasma плазма
possible можливий
pressure тиск
property властивість
quantity кількість
random випадковий
relation відношення
research дослідження
rotate обертати
shape форма, обрис
simultaneously одночасно
solid твердий
substance речовина, матерія
suppose гадати, вважати
teach вчити
universe всесвіт
various різний
vessel посуд
volume обсяг
well-known відомий
wire дріт, провід

 

Exercise 1. Read and translate the text.

Four States of Matter: Solid, Liquid, Gas, Plasma.

A number of Greek philosophers (about 490-430 before our era) taught that the material universe was built of four "roots": earth, water, air and fire. This in modern terminology may be compared with the four states of mat­ter: solid, liquid, gaseous and the plasma state, respecti­vely.

One might ask: "Can every substance exist in all of these four states?" Many substances can do at various-times exist in more than one of the four possible states. That state depends on the substance itself as well as on its volume, temperature and pressure. Ordinary air, for example, condenses completely to a liquid if the tempera­ture is lowered to 196° below zero Centigrade. It would become a solid provided the temperature were further lowered to – 218° C.

Suppose that one could live in a world where the ave­rage temperature were 250° C. At our ordinary pressures, water and ether would be in a gaseous state. On the other hand, was the temperature — 250° C, the substances just mentioned would be solids at that very atmospheric pres­sure. Of no less interest is the fact that the only liquids existing would be hydrogen and helium.

If we think of the substance that we call "water" we generally think of it as a liquid. It does not mean that that is the only possible state in which water does exist. That the liquid stale is the normal state for water is a well-known fact. But water, as anyone must know, can also exist in a gaseous state, i.e., as steam and as a solid, i.e. ice.

The same number and kind of molecules are present in a kilogram of water, steam or ice. However, these molecu­les move differently in each of the above-mentioned sta­tes, hence, their widely varying characteristics.

Let us turn our attention first to solid bodies. The mo­lecules of solids are able to move only through a limited range. The motion of the molecules of a solid is harmonic in type. The molecules move between fixed limits back and forth on either side, of an "average" position and sel­dom pass outside those limits. It is a solid that has both volume and shape.

The reader should certainly know that the molecules of liquids are in a state of constant, random motion. Howe­ver, there are attractive forces exerted on each molecule by the surrounding molecules. Thus, a given molecule is free to move within the liquid itself but is not likely to leave its surface unless it moves very fast. The rather lar­ge forces of attraction exerted on that molecule by the surrounding molecules serve to fix the volume of a given liquid although its shape is changeable.

It is to the gaseous state that we shall turn our atten­tion now. Experiment shows us that there is very little attraction between the molecules of any gas. The gas molecules move, with an almost perfect freedom, very little force being exerted on one molecule by the molecules sur­rounding it. The molecules move rapidly in every di­rection, colliding with one another, expanding to occupy every portion of the container, bombarding the walls of the container. Gases, therefore, have no fixed volume or sha­pe. Their volume and shape depend on the vessel that contains them.

The fourth state of matter, the plasma, consists of neu­tral atoms, ionised atoms and electrons.

Exercise 2. Give Ukrainian equivalents of the following words.

liquid, philosopher, teach, universe, earth air, gaseous, respectively, substance, various, although, hence, inversely, evident, affect.

 

Exercise 3. Give English equivalents of the following words.

градус, Цельсій, сила, провід, увага, звичайно, відомо, ємність (посудина), матерія, заряд.

 

Exercise 4. Answer the questions.

1. What are the four states of matter?

2. What did the Greek philosophers teach?

3. Do many substances exist in more than one of the four possible states?

4. What does the state of a substance depend on?

5. At what temperature does ordinary air condense?

6. Does water exist in a gaseous state?

7. Why has a solid both volume and shape?

8. What does the shape of a gas depend upon?

9. What does the plasma consist of?

 

Exercise 5. Translate the following sentences.

1. If a solid is heated it will expend.

2. On our planet plasma has to be generated by special physical processes and under special conditions.

3. It is the molecules of liquids that are in a state of constant random motion.

4. Air does condense completely to a liquid when the temperature to a liquid when the temperature is lowered to – 196 C.

5. Life on our planet would be impossible unless there were water.

6. Of particular interest is the fact that we are faced with limit less possibilities in future applications of the plasma.

7. It is plasma properties that our physicists study.

 

Exercise 6. State if the following sentences are true to the fact or false. Correct the false sentences.

1. There are two states of matter, namely liquid and gas.

2. Many substances exist only in one state.

3. The molecules of solids are in a state of constant, random motion.

4. There is very little attraction between the gas molecules.

5. The plasma consists of neutral atoms, ionised atoms and electrons.

 



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