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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 cooler spot to a warmer 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;
availability – available;
heavy – heavily;
recovery – recover – recovered;
exist – existence – existent;
heat – heated – heatedly – heater – hot.
Exercise 47. Work in pairs. Make a question for each answer below with reference to the text. Use the question word given in brackets.
1. Energy is measured in many ways. (How?)
2. Heat is a type of energy. (What?)
3. James Joule lived from 1818 to 1889. (When?)
4. Energy has always existed in one form or another. (What?)
5. Warm air rises because it is lighter. (Why?)
6. It becomes kinetic energy. (What kind?)
7. The directions change during the night time. (When?)
8. We use heat for a lot of things. (What … for?)
Exercise 48. Give antonyms of the words given below.
Light, hot, daytime, outside, safe, progressive, final, empty, absorb, look into, create, turn on.
Exercise 49. Insert prepositions wherever necessary.
1. Street lamps use electrical energy to light our way … night. 2. Energy is measured … joules. 3. English scientist James Joule lived … 1818 … 1889. 4. Ukrainian officials have announced new projects and possibilities of the transit … Caspian oil and gas … EU countries. 5. The pipeline is used … supplying to European markets instead … its operating … the reverse direction. 6. A thousand joules is equal … a British thermal unit. 7. The meeting was held … the beginning of October. 8. Energy can be transformed … another sort of energy. If you stir a pan … soup … the stove … a metal spoon, the spoon will heat up. 9. You should wear light and white clothes … summer. 10. There is a possibility … establishing transit of electricity … Ukraine … Baltic countries.
Exercise 50. Change the following sentences into the Passive Voice.
1. Around the world, scientists measure energy in joules. 2. Nobody can create or destroy energy. 3. One can find energy in a number of different forms. 4. We use the pipeline for supplying oil. 5. Our country will transit electricity to Baltic countries through Belarus. 6. Metals conduct heat energy. 7. Our body uses stored energy to do work. 8. You can easily understand the information. 9. The officials have announced new projects. 10. GUEU consortium is developing the project for gas supplying. 11. We plan to implement the project in three stages.
Exercise 51. Put the verbs in brackets into the correct form of Present Perfect or Past Simple.
1. James Prescott Joule who lived in the 19th century (discover) that heat is a type of energy. 2. Recently, Ukrainian officials (announce) that a new gas pipeline will transfer Caspian oil and gas to Europe. 3. The volume of gas transit through Ukraine (be) 120 bn cu. m last year. 4. They already (set) transit tariffs through bilateral talks. 5. They (develop) the project under the leadership of the British company. 6. Energy always (exist) in one form or another. 7. Some studies (indicate) that the cost of producing ethanol exceeded the value of the fuel produced. 8. The price of oil (rise) last month. 9. The need for alternatives to gasoline (become) very urgent. 10. The scientists (introduce) technologies for integrating and maximizing the advantages of such energy sources as earth, wind and light.
Exercise 52. Answer the questions on text 4.
1. What forms of energy can be found around us?
2. How is energy measured?
3. What is British thermal unit?
4. What is potential energy?
5. What is kinetic energy?
6. How does heat energy move?
7. What is the definition of a Joule?
8. When does conduction occur?
9. What is convection?
10. What surfaces can absorb radiation?
Exercise 53. Translate into English.
1. Сонячне випромінювання є рушійною силою кругообігу води в природі. 2. Енергія води, або гідроенергія відноситься до перетвореної енергії сонця. 3. Перетворення сонячної енергії в електричну здійснюється за допомогою сонячних батарей. 4. Темна поверхня поглинає сонячне випромінювання і, навпаки, світла поверхня відбиває сонячні промені. 5. У березні 2006 року Кабінет Міністрів України затвердив енергетичну стратегію України на період до 2030р. 6. Вчені детально проаналізували статистичні дані споживання паливно-енергетичних ресурсів. 7. Процес перетворення целюлози в етиловий спирт відносно дорогий і неефективний. 8. Людство дуже скоро може витратити запаси вугілля і нафти, які були накопичені у надрах землі на протязі сотень мільйонів років. 9. Сонячне світло відбивається або поглинається. 10. Існують різні види енергії: хімічна, електрична, механічна, ядерна та інші. 11. Ми зробили ще дуже мало, аби зменшити нашу залежність від нафти, найбільш ефективного виду палива.
Exercise 54. Discuss the following questions in groups.
1. Is it possible to heat a space station by radiators?
2. Why are tyre-covers changed so often during “Formula 1” motor-race?
3. Which radiators heat better: aluminum or iron?
4. Why is it cooler near the sea in summer and warmer in winter?
Exercise 55. Compose dialogues on “Thermal Energy”.
Exercise 56. Memorize the following words and word combinations to text 5.
Heat exchanger – теплообмінник
shell and tube heat exchanger – кожухо-трубчатий теплообмінник
medium (pl. media) – середовище
wall – стінка, бар’єр
direct – безпосередній
refrigeration – охолоджування, заморожування
petro-chemical – нафтохімічний
refinery – нафтоочисний завод
arrangement – розміщення; розташування
parallel flow – паралельний потік
counter flow – зворотний потік
cross flow – поперечний потік
roughly – приблизно
resistance – опір
performance – характеристика, продуктивність
fin – радіаторна пластина; ребро
corrugation – рифлення
channel – направляти каналом
induce – викликати; спричиняти; заставляти
turbulence – турбулентність
mean temperature – середня температура
log mean temperature difference – середній логарифм відношення температур
tube – труба
bundle – в’язка, жмут, пучок
plain – плоский, плаский
longitudinal – повздовжній
robust – міцний
take into account – враховувати
pitch – крок
layout – розміщення
baffle – переборка; дефлектор
wrought iron – пудлінгове залізо
foul (up) – засмічувати(ся), забивати(ся
scale – накип, окалина
biofouling – утворення біологічного осаду
prevail (over) – отримувати перемогу; справлятися, упоратися.
Exercise 57. Read and translate text 5. Divide it into logical parts and write a topical sentence for each part.