Передмова (стр. 6 )

There are many statements of the second law which use different terms, but they are all equivalent. The simplest formulation of the second law is: heat cannot flow spontaneously from a lower-temperature material to a higher-temperature material. It is obviously true from everyday experience. For example, in a refrigerator heat flows from cold to hot, but only when electrical energy is added. Note that from the mathematical definition of entropy, a process in which heat flows from cold to hot has decreasing entropy.

The formulation of the second law given by Lord Kelvin is the following:

It is impossible to convert heat completely into work. It is impossible to extract energy by heat from a high-temperature energy source and then convert all of the energy into work. Thus, a heat engine with 100 % efficiency is thermodynamically impossible.

The third law of thermodynamics is about absolute zero temperature.

As a system asymptotically approaches the temperature of absolute zero, all processes virtually cease and the entropy of the system asymptotically approaches a minimum value. It is impossible to reach the temperature of absolute zero by any finite number of processes.

Exercise 33. Define the parts of speech and translate the words.

a) designate – designation; observe – observation – observer; measure – measurement; heat – heater; transmit – transmission; generate – generator – generation; extract – extraction; equilibrate – equilibrium; relate – relation; convert – converter – conversion; apply – application; emit – emitter – emission; transform – transformation – transformer.

b) equivalence – equivalent; spontaneity – spontaneous; practice – practical; power – powerful; mechanic – mechanical; validity – valid; observation – observable; variety – various; practice – practical; use – usual; base – basic; difference – different.

c) usual – usually; continuous – continuously; spontaneous - spontaneously; obvious – obviously; practical – practically; potential - potentially; basic – basically; converse – conversely; equal – equally; virtual – virtually; increasing – increasingly; different – differently.

Exercise 34. Give the initial form of the following words. Define the parts of speech and translate.

a)  better, lower, higher, hotter, less, greatest, older, more, best, worse, most, worst, farther, further, elder.

b)  written, known, held, lost, left, decreased, converted, given, found, situated, driven, spread, undergone, been, applied.

Exercise 35. Translate and comment upon the following verb forms.

Was coined; can be applied; is assumed; being studied; can store; may be lost; does; will be decreasing; have been explained; have reached; is converting; being defined; are to be; must have written; stopped increasing.

Exercise 36. Translate the following word combinations into Ukrainian.

Spontaneous emission, current research, thermal equilibrium, measurement of temperature, macroscopic properties, mathematical definition, formulation of the law, high-temperature energy source, heat engine, absolute zero, finite number of processes, engine efficiency, leading scientists.

Exercise plete the sentences with English equivalents of the words in brackets.

1.  Boyle and Hooke noticed a correlation between (тиском), (температурою) and (об’ємом).

2.  Boyle’s Law states that pressure and volume are (обернено пропорційні).

3.  Energy may be lost by the system when it does (механічну роботу) on its surroundings.

4.  It is impossible to (перетворити) heat completely into work.

5.  Thermodynamics describes how systems (реагують) to changes in their (оточенні).

6.  The starting point for most thermodynamic considerations are (закони термодинаміки).

7.  By watching (клапан) rhythmically move up and down, Papin conceived the idea of (поршневого двигуна).

Exercise 38. Work in pairs. Translate the following questions and answer them.

1. Що вивчає термодинаміка?

2. Як визначаються «система» і «навколишнє середовище» у термодинаміці?

3. Скільки існує законів термодинаміки?

4. Якого вченого можна вважати засновником термодинаміки?

5. Що таке термодинамічна рівновага?

6. Чи існує багато формулювань другого закону термодинаміки? Чим це пояснюється?

7. Як відбувається теплообмін між предметами різної температури? Наведіть приклади.

8. Що таке ентропія?

9. Яке співвідношення існує між тиском, температурою і об’ємом?

Exercise 39. Say whether the following statements are true or false. Correct them if necessary.

1.  There are three laws of thermodynamics.

2.  The first engine was built by Boyle and Hooke?

3.  Sadi Carnot designed the world’s first vacuum pump.

4.  Heat moves from a low-temperature source to a high-temperature source.

5.  The new textbook on thermodynamics has already been written.

6.  The system gains energy when it does mechanical work.

7.  It is possible to reach the temperature of absolute zero by any finite number of processes.

8.  A thermodynamic system can’t store or hold energy.

9.  Internal energy is always conserved.

10.  A heat engine with 100 % efficiency is thermodynamically possible.

Exercise 40. Speak on «Four Laws of Thermodynamics».

Exercise 41. Memorize the following words and word combinations to text 4.

Chemical energy – хімічна енергія

heat energy – теплова енергія

radiant energy – енергія випромінювання

Btu (British thermal unit) – британська теплова одиниця

invent – винаходити

sea level – рівень моря

equal – однаковий; дорівнювати

match – сірник

weigh – важити; зважувати

height – висота

exist – існувати

destroy – знищувати

flash light – ручний електричний ліхтар

occur – відбуватися

stir – розмішувати

convection – конвекція

empty – порожній

Exercise 42. Read and translate text 4. Make up the plan of the key ideas.

Text 4. What is heat and how it moves

Energy causes things to happen around us. Look out of the window. During the day the sun gives out light and heat energy. At night, street lamps use electrical energy to light our way. When a car drives by, it is being powered by gasoline, a type of stored energy. The food we eat contains energy. We use that energy to work and play.

Energy can be found in a number of different forms. It can be chemical energy, electrical energy, heat (thermal) energy, light (radiant energy), mechanical energy and nuclear energy.

Energy is measured in many ways. One of the basic measuring blocks is called a Btu. This stands for British thermal unit and was invented by, of course, the English. Btu is the amount of heat energy it takes to raise the temperature of one pound of water by one degree Fahrenheit, at sea level. One Btu equals about one blue tip kitchen match. It takes about 2,000 Btus to make a pot of coffee. Energy also can be measured in joules. A thousand joules is equal to a British thermal unit.

1,000 joules = 1 Btu. The term ‘joule’ is named after an English scientist James Prescott Joule who lived from 1818 to 1889. He discovered that heat is a type of energy. One joule is the amount of energy needed to lift something weighing one pound to a height of nine inches. Around the world, scientists measure energy in joules rather than Btus.

Heat is a form of energy. We use it for a lot of things, like warming our homes and cooking our food. Heat energy moves in three ways:

1.  Conduction;

2.  Convection;

3.  Radiation.

Conduction occurs when energy is passed directly from one item to another. If you stirred a pan of soup on the stove with a metal spoon, the spoon will heat up. The heat is being conducted from the hot area of the soup to the colder area of spoon. Metals are excellent conductors of heat energy. Wood or plastics are not. Convection is the movement of gases or liquids from a warmer spot to a cooler spot. The wind we feel outside is often the result of convection currents. You can understand this by the winds you feel near the ocean. Warm air is lighter than cold air and so it rises. During the daytime, cool air over water moves to replace the air rising up as the land warms the air over it.

During the night time, the directions change – the surface of the water is sometimes warmer and the land is cooler.

Radiation is the final form of movement of heat energy. The sun’s light and heat cannot reach us by conduction or convection because space is almost completely empty. There is nothing to transfer the energy from the sun to the Earth.

The sun’s rays travel in straight lines and are called heat rays. When rays move that way, it is called radiation. When sunlight hits the Earth, its radiation is absorbed or reflected. Darker surfaces absorb more of the radiation and lighter surfaces reflect the radiation. So you would be cooler if you wear light or white clothes in summer.

Exercise 43. Translate the following words and word combinations.

Stored energy, nuclear energy, named after, amount of energy, flash light batteries, potential energy, kinetic energy, excellent conductors, warm air, daytime, convection, radiation, night-time, final form, sun’s rays, heat rays, light clothes, sunlight, conduction.

Exercise 44. Write the verbs related to the following nouns. Translate the pairs.

Measurement, invention, discovery, weight, transformer, creation, existence, storage, conduction, radiation, movement, change, heat, transfer, reflection, absorption, practice, content, energy, difference, provision, discovery, warmth, passage, cold, direction.

Exercise 45. Write the nouns related to the following verbs. Name the suffixes used to form nouns. Translate the pairs.

Weigh, destroy, occur, apply, recover, convert, substitute, estimate, light, amount, invent, create, feel, replace, travel.

Exercise 46. Identify by suffixes: a) nouns; b) adjectives; c) adverbs; d) verbal forms. Translate them.

Conversion – convertible – converting;

equal – equality – equally;

refinement – refined – refiner;

significance – significant – signification – significantly – signify;