WORD FORMATION: Verbs and Nouns of Reporting

Form nouns from the following verbs and use them in Ex.11

refuse − refusal     demand −              offer −              promise − agree −                    threaten −             claim −             warn − encourage −            prohibit −            invite −            admit − permit −                   deny −                  complain −      discourage −

 

GRAMMAR PRACTICE:  Gerund or Infinitive (GR-19, 206)

9. Choose Gerund or Infinitive to complete the sentences.

1. They did not agree to repeat/repeating the experiment.

2. The head of the laboratory did not allow the staff to have/having lunch time when they like.

3. The technician didn’t admit to use/using the wrong spare parts.

4. They did not promise to deliver/delivering the equipment free of charge.

5. The administration of the research institute does not encourage employees to take/taking their vacations in August.

 

Rewrite the sentences using the verbs of opposite meaning.

Example:  They did not agree to repeat the experiment.

They refused to repeat/repeating the experiment.

WRITING

11. Write a letter of complaint about the faulty equipment delivered at your laboratory . Use verbs and nouns from ex.  8.

 

CONFUSABLES

Translate the sentences paying attention to the meaning of the words in the box.

used         used to do            used to doing   get used to

1. In June 1997 Andrew Wiles received the prestigious Wolfkehl prize. The reward – established in 1908 by a German industrialist for cracking the baffling  Fermat’s last theorem – used to be worth $ 2 million. By the summer of 1997 it reduced to mere $ 50.000 resulting from the hyperinflation.

2. Mendeleyev’s intuition had been right, however, and atomic number was used successfully to assign a place in an expanded table for the noble gases – helium, neon, krypton, radon, and xenon – which were discovered in the 1890s.

3. Fermat’s contemporary mathematicians got used to being challenged with theorems which he claimed to have solved.

 

UNIT 13 THERMAL PHYSICS

1. Read the text and decide whether the following sentences are true or false:

a). Liquids are poorer conductors of heat than gases.

b). Vacuum is the best insulator

c). How well a substance conducts heat doesn’t depend on its structure and its molecular bonds.

                                        Heat Conduction

We know that heat is accomplished by three methods: conduction, convection and radiation. If heat energy is transferred through space by means of electromagnetic waves, the process is known as radiation. When heat exchange is caused by the bulk motion of gas or liquid, we say that it happens due to convection. Though there is the third way – conduction.

If a silver and a wooden spoon are dipped simultaneously into a glass with hot water, in two minutes you will not be able to touch the handle of a silver spoon as it will be hot, but that will not be the case with the handle of the wooden one. Why?

The reason is that the kinetic energy of the molecules at the hot end of the silver spoon is readily transferred from one molecule to the next. That is, the kinetic energy of molecules is transferred from one molecule to another through collisions. However, this is not the case with wood. The transfer of heat from one molecule to the next is known as conduction. When heat is transferred in this way, it is said to be conducted. Materials in which this occurs readily are said to be good conductors of heat.

All metals are good conductors of heat. In metals, in addition to molecular collisions, there are a large number of “free” electrons (not permanently bound) that can move and that can take part in the transfer of heat. These electrons contribute significantly to heat transfer in metals.

Liquids and gases are in general relatively poor thermal conductors. Liquids are better conductors of heat than gases because their molecules are closer together and collide more often. Gases are poor conductors because their molecules are relatively far apart and collisions do not occur as often. Substances that are poor thermal conductors are known as thermal insulators, they prevent heat from escaping because their molecules do not transfer heat readily from one to the next. Still air is one of the poorest conductors: consequently it is one of the best insulators.. It has been noticed, that any material which encloses plenty of air (is porous) is a good insulator, for example: cork, wood, fibre-glass, asbestos, plastic foam (Styrofoam).

How are these properties of materials used in our everyday life? We make cooking pots and pans from metals, because they conduct heat readily to the foods inside, while the handles are made from the wood or plastic, thus preventing our hands from burning. Pot holders are also made of cloth, a poor thermal conductor, for the same reason. Fibre-glass insulation is used in the walls and attics of our houses. Another example is a double window in our house: there is a layer of still air between two glasses, as still air is a good insulator, subsequently, the double window prevents the heat from escaping.

It is evident that the process of conduction as well as convection requires some medium, while radiation can take place in both, gas and vacuum.

 

2. In the text find equivalents to the following phrases:

- тепло передается таким образом

- говорят, что оно передается за счет теплопроводности

- электроны вносят значительный вклад в теплопроводность металлов

- относительно плохие проводники тепла

- вещество, которое содержит много воздуха

- окна с двойными рамами хорошо удерживают тепло

- стекловата используется для утепления стен и чердаков наших домов

- неподвижный воздух является хорошим изолятором тепла

 

VOCABULARY STUDY

3. Translate the following words and word combinations:

conduct, conduction, conductive, heat conductivity, electrical conductivity;

penetrate, penetrative, penetration;

relate, relation, relative, relatively, relativity, theory of relativity;

insulate, insulator, insulating, insulation;

prevent, preventive, prevention, to prevent heat from escaping;

radiate, radiating, radiation, radiator;

heat, heating, central heating system;

5. Match synonyms to the underlined words:

a) artificial b) admit c) enormous d) feature e) evident f) permanent g) simultaneously

1. In winter our houses need a continuing supply of heat.

2. It is clear that the results of this experiment are positive.

3. Man-made lakes are formed behind the dams.

4. You have to start two motions at the same time.

5. The characteristic property of the wood is its poor conductivity of heat.

6. Dams are very huge structures.

7. We have to notice that this law is valid under these conditions.

 

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