44726

Complex Subject

Конспект урока

Иностранные языки, филология и лингвистика

The low temperture physics dels with vrious phenomen occurring tempertures in the region of bsolute zero 273єC. The lowest temperture on Erth is known to hve been registered in the ntrctic bout 80єC. Still lower tempertures re climed to be found on other plnets.

Английский

2013-11-13

76.71 KB

6 чел.

     UNIT 14

Grammar: Complex Subject

TEXT 14 A

    Superconductivity

Low temperature physics is know to be making rapid progress. Greatexperemental and theoretical programmes are under way in this branch oh physics. Scientists all over the world take part in international conferences of physicists. Where they discus problems of crating new superconductors with high resolving properties.  The low temperature physics deals with various phenomena occurring at temperatures in the region of absolute zero (-273єC). The lowest temperature on Earth is known to have been registered in the Antarctic about -80єC. Still lower temperatures are claimed to be found on other planets. On Saturn, for instance, it reaches, on Uranus, on Neptune. On Plutothe planet most remote from the sun- the temperatures appears to be belowC. Even this, however, is believed not to be the limit. A temperature ofєC has been found to be possible in nature. In laboratory experiments scientists have achieved a temperature, which differs from absolute zero by 1/10,000 of a degree.

Having learnt to control heat, man has multiplied its potential many times over, learned to cut and melt metal and found many other useful applications for it. Cold is considered to be quite useful.

The study of different substances at low temperatures has revealed many interesting phenomena. One of the most amazing (surprising) was superconductivitythe complete loss of resistance to electrical current. This property has been found in more than 20 metals. If an electric current is sent through a ring of cooled metal of this type, it will circulate for a very long time.  

Superconductivity has long been the subject of pure theory and it seemed that it would never be possible to apply it in practice. However, instruments have been developed using this phenomenon.

Of particular interest are the superconductive alloys widely applied in the development of superconductive magnets, which make possible, with a small expenditure of power, to obtain permanent magnetic fields of scores and hundreds of thousands of oersteds1 .

Of great interest are recent theoretical studies that indicate the possibility of developing superconductors retaining their properties at room and even higher temperatures. Their practical application could open up a new chapter in the use of electric power. It could multiply the efficiency of electrical machines and save billions of kilowatt hours in transmitting power over long distances.

     N O T E S       

1.oersted [:sted] —. ерстед , 2.одиниця магнітного опору.

         

Answer these questions:

1. What does this article deal with 2. What phenomena does low temperature physics deal with 3. At what temperatures do these various phenomena occur 4. Do they occur at temperatures in the region of absolute zero or not 5. What lowest temperature on Earth has been registered in the Antarctic 6. Are still lower temperatures claimed to be found on other planets 7. What is the temperature on Saturn 8. How many degrees of cold does the temperature reach on Uranus 9. How many degrees of cold does the temperature reach on Neptune 10. How many degrees of cold does the temperature reach on Pluto 11. Is°C believed to be the limit of cold 12. What temperature has been found to be possible in nature 13. What kind of temperature have scientists achieved in laboratory experiments 14. What has man learned to do with metal 15. What other applications has man found for metals 16. Is cold considered to be quite useful or not 17. What was the result of the study of different substances at low temperatures 18. What is superconductivity 19. In how many metals has superconductivity been found

EXERCISES

I. Translate these word combinations into Ukrainian:

temperature limit, limit temperature, liquid helium, solid helium, resistance loss, metal conductivity, room temperature, cooling system, laboratory experiments, television transmitters, power transmission, wave oscillation, low temperature physics, low temperature use, long distance transmission, large temperature differences, limit temperature use, power plant construction, transmission line efficiency, electrical control systems, cosmic radio communication, complete resistance loss, scientific research work, instantaneous frequency variation

II. Translate the following words, paying attention to the meaning of the prefixes super-, over- :

superconductivity, superconductive, superconductors, superhard, superfluidity, supersonic, overload, overflow

III. Translate these word combinations, paying attention to different meanings of the following words:

body, solid, field, develop, fall, range, degree

the body of a man, the body of a car, the body of a meteor; a solid state of matter, a solid building, a solid argument; an electric field, an oil field, coal fields, diamond fields; to develop science, to develop different theories, to develop existing motors, to develop natural resources, to fail in an exam, a complete failure, the failure of a motor; a range of 20 kilometers, a range of problems, wave range, a short range.    

IV. Translate these word combinations:

remote control, to control heat, to find useful applications, to subject to high pressure, to subject to high temperature, to occur at temperatures, in the region of absolute zero, to reach out to absolute zero, to become solid at temperatures close to absolute zero (near to), to fill quickly, to fill slowly, a surprising property, an important property, to apply superconductivity in practice, to apply superconductive alloys, to apply superhard metals, to deal with different phenomena, to deal with different problems, this book deals with, preliminary designs, preliminary data.

V. Find synonyms in the following sentences and write them out:

. Let’s choose particular substances for our experiments. 2. It is necessary to select special techniques in dealing with this phenomenon. 3. The new express train runs at a speed of 160 km.p.h. 4. This is a fast train. 5. Solid helium is obtained by cooling and simultaneously subjecting it to high pressure. 6. One can get solid helium by cooling and at the same time by subjecting it to high pressure.

 VI . Complete the following sentences:

  1.  The low temperature physics deals with
  2.  In laboratory experiments scientists have achieved a temperature which
  3.  Having learnt to control heat, man learned to
  4.  Cold is considered to be
  5.  If an electric current is sent through a ring of cooled metal of this type,
  6.  Superconductivity has long been the subject of.
  7.  Of particular interest are the superconductive alloys
  8.  Of great interest are recent theoretical studies that

VII. State whether the following statements true or false:

  1.  The lowest temperature on earth is known to have been registered in the Antarctic (about0єC)
  2.  A temperature of  –єC has been found to be impossible in nature.
  3.  Cold is considered to be of no importance.
  4.   The study of different substances at low temperatures has revealed many interesting phenomena.
  5.  It will never be possible to apply superconductivity in practice.
  6.  Recent theoretical studies indicate the possibility of developing superconductors retaining their properties at room and even higher temperatures.


TEXT 14 B

Liquid helium surprises 

Translate the text using a dictionary

1. All solid bodies become brittle while liquids and gases become solid at temperatures close to absolute zero. There is only one gashelium which fails to solidify on cooling alone. Solid helium is obtained by cooling and simultaneously subjecting it to high pressure. 

. At temperatures near to absolute zero, liquid helium reveals a surprising propertysuper fluidity. This phenomenon, discovered by Pyotr Kapitza, defies all conventional concepts of physics. For instance, if liquid helium is poured into a vessel it immediately climbs up the internal walls of the vessel and overflows. On the contrary, if an empty cup is partially submerged in liquid helium, the latter quickly fills it to the level of the surrounding liquid.  

. The range of investigations into low temperature has grown and is certain to grow with the progress of physics. Low temperatures are now used in certain studies in nuclear physics, radio-physics, electronics, optics, chemistry and biology. Particularly wide application, however, has been found for them in diverse research into the physics of solids.

      

TEXT 14 C

Cryogenic propellants 

Give a summary of the text

At ordinary temperatures hydrogen and oxygen, and some other potential propellants, for example fluorine, are gases and not until they are in a gaseous state do they undergo chemical reaction in the rocket engine. But in the gaseous form they have such low densities that it would require extremely large tanks to store them in the rocket vehicle. The storage of propellants in the gaseous form is thus completely impractical. It is for this reason that the substances mentioned above are stored as liquids at very low temperatures; they are consequently referred to ascryogenic propellants” (fromKryos” –“ice coldin Greek).

In the liquid form, the densities are much greater than in the gaseous state, and consequently the propellant tanks can be much smaller and less massive. This advantage is offset, however, by the low temperature required, so that liquid hydrogen, liquid fluorine, and liquid oxygen cannot be stored in the rocket tanks for long periods of time, nor can they be used without special precautions.

Such nonstorable, cryogenic propellants must be loaded into the tanks shortly before the rocket is launched.

Simultaneously compressing and cooling the gases to the required low temperature make the cryogenic liquids. They are then stored and transported, with moderate loss, in special vacuum-jacketed tanks. These containers are designed on the same principle as the familiar vacuum- bottles used to store hot or cold liquids in the home.

Here you can see the temperatures at which a number of cryogenic liquids, of possible use as propellants, liquefy at ordinary atmospheric pressure. These temperatures represent the conventional boiling points of the various liquids. By increasing the pressure in the container the boiling points can be raised to a certain extent, so that the liquid form can exist at somewhat higher temperatures. It can be seen, however, that the temperatures required to produce and store cryogenic propellants are extremely low by normal standards.  

   

   Boiling points of cryogenic propellants    

Substance

      

        Density

(Grams/cu cm)

                        Boiling points

     єC

єF

    Hydrogen

Oxygen

Fluorine

0.07

.1

1.5

       -253

-183

-188

-423

-298

-307

In order to avoid the problems associated with cryogenic propellants and to make rockets ready for launching at all times, storable liquid propellants have been developed. 


 

А также другие работы, которые могут Вас заинтересовать

2475. Фінанси. Електронний курс лекцій 544.17 KB
  Сутність фінансів, їх функції і роль. Принципи структурування фінансової системи. Організаційна структура фінансової системи. Управління фінансовою системою та фінансова політика. Зовнішні і внутрішні фінансові відносини. Суть і склад державних фінансів. Бюджет держави: сутність і призначення. Пряме та непряме оподаткування в Україні. Страхування і страховий ринок. Визначення фінансового ринку і його елементи.
2476. Економічна статистика 731 KB
  Основи класифікації економічної статистики. Система національних рахунків – методологічна основа економічної статистики. Показники статистики населення. Завдання статистики населення. Показники чисельності та складу населення. Статистика використання робочого часу. Статистика науково-технічної та інноваційної діяльності. Оцінка рівня інфляції, її використання для порівняльного аналізу вартісних показників. Статистика доходів сектору домашніх господарств. Джерела інформації про споживання населенням.
2477. Основы аудита. Принципы профессиональной этики аудита 244 KB
  Структура договора на проведение аудиторской проверки. Предплановая (преддоговорная) деятельность. Документация аудитора. Обзор событий, произошедших после даты составления баланса. Планирование аудиторской проверки, ее назначение и принципы. Критерии отнесения организации к обязательному аудиту. Основные этапы становления и развития аудита в России.
2478. Теория общей химии с элементами методики преподавания 413 KB
  Экспериментальные (качественные) задачи по химии. Подготовка учителя к уроку. Понятие об энтропии и изобарно-изотермическом потенциале. Самостоятельная работа учащихся по химии. Задачи курса химии средней школы. Технические средства обучения. Структура нуклеотидов и нуклеозидов.
2479. Акушерство и гиникология. Аборты и гинекологическая помощь 1.27 MB
  Аборты, акушерская помощь. Агалактия и гипогалактия. Бесплодие и яловость животных. послеродовой парез. Аборт - прерывание беременности с последующим рассасыванием зародыша, мумификацией, мацерацией, путрификацией либо изгнанием из матки мертвого неизмененного плода (выкидыша) или незрелого живого плода (недоноска).
2480. Теорія адміністративної відповідальності при порушенні митних правил 289.5 KB
  Адміністративна відповідальність за порушення митних правил. Завдання, принципи та функції адміністративної відповідальності. Поняття, завдання та принципи провадження в справах про порушення митних правил. Опротестування постанови по справі про порушення митних правил. Свідки та поняті у справах про порушення митних правил.
2481. Высшая математика. Исследование интегралов и теоремы гипотез 147.5 KB
  Неопределённый интеграл и его свойства. Вычисление пути, пройденного точкой. Основные понятия и свойства числовых рядов. Разложение функций в ряд Тейлора. Формула Байеса (теорема гипотез). Формула Бернулли. Определение комплексного числа. Действия над комплексными числами в алгебраической форме.
2482. Організація готельного господарства та туристичної діяльності 895.5 KB
  Типізація готельного господарства. Характеристика ПГГ для масового туризму. Особливості організації праці в готелі. Культура обслуговування. Сутність гостинності. Прийом, розміщення мешканців. Використання платіжного документа. Обслуговуючі господарства. Ресторан при готелі.
2483. Методы измерения материалов и процессов 828.5 KB
  Методы измерения ферромагнитных свойств. Методы определения термического расширения, дилатометрические исследования. Антифрикционные материалы. Материалы с высокими упругими свойствами. Материалы с малой плотностью и высокой удельной прочностью. Последующая обработка гальванопокрытий. Формирование сплошных покрытий.