Look at these pictures. What physical phenomenon unites these pictures?



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Module 11

Lesson 1

Look at these pictures. What physical phenomenon unites these pictures?



maglev-train_maxresdefault06112015_01superconductor

1 Answer these questions


1 What do you know about superconductivity?

2 When was superconductivity discovered?

3 What is a superconductor?
2 Read the information and say what current applications of superconductivity you know.
The phenomenon of superconductivity has always been very exciting, both for its fundamental scientific interest and because of its many applications. The discovery in 1980s of high-temperature superconductivity in certain metallic oxides sparked even greater excitement in the scientific and business communities. Many scientists consider this major breakthrough to be as important as the invention of the transistor. For this reason, it is important that all students of science and engineering understand the basic electromagnetic properties of superconductors and become aware of the scope of their current applications.
3 Complete the definitions, using the prompts.
resistance a substance/ the degree/ the flow of electricity/to which/prevents/through it

resistivity electrical/ of/ resistance/ a measure/ of a substance

conduct v (physics) to flow/ electricity or heat/ through/to allow

conductor electricity/a substance/ or heat/ that allows/ to pass/ along it or through it

superconductor resistance/ a/ zero/ with/electrical/ material

semiconductor such as silicon,/ a substance/ to flow/ that/ some/ allows/ electricity/

through it/ to flow



insulator allow/ a substance/ that/ does not/electricity/ to pass/ through
4 Choose the correct alternative.
1 Copper/gold/silver is the most electrically conductive element

2 Aluminum is a good superconductor/ conductor/semiconductor

3 Mercury becomes a conductor/ superconductor/ semiconductor at very low temperatures

4 Although silver/copper/ is the best conductor, copper / silver/ is used more often

in electrical applications because copper /silver is less expensive

5 Gold /silver has a much higher corrosion resistance

6 Glass is a good conductor/ superconductor /insulator

5 Work in pairs and discuss the questions.
1 What is the most conductive element?

2 What is an electrical insulator? Name some common insulators.

3 How does a conductor differ from an insulator?

4 What makes water a good conductor of electricity?

5 What elements are used more often as conductors in electrical applications? Why?

6 Why is silver the best conductor?


6 Decide which part of speech the words belong to.
Superconductivity, superconductor, superconductive, superconducting; physics, physical, physicist, physically; resistivity, resistance, resistant, resistor; differ, difference, different, differentiate, differently, differential; apply, appliance, application, applied, applicable;

measure, measureless, measurement; powerless, power, powerful, powerfully.


7 Watch the first part of the video “Adventures at Nanoscale: Superconductivity” (5:08 min) and answer the questions. Use the prompts.

Useful notes

strand v (usually passive) – застрять на дороге, сесть на мель

flashlight - фонарик

a bunch of people - группа людей
1 Why was a group of high school friends stranded on a country road?

car/ break/ down

2 What did they decide to do?



town/ near/ walk

3 Why couldn’t they call for help?



phone/ not work/ walk/ clear phone signal

4 What was the story about in the science blog?

/ superconductors/use/ less energy/regular conductors

5 What happened with Ellie and Eddie?

become /small/ turn /copper /atom/

6 Where did they find themselves?



inside / one/ atoms/ copper/ wire

7 What explanation was given to the term ’regular conductor in the video?



material/ allow/ electron/ freely/ move /around

8 Watch the second part of the video Adventures at Nanoscale: Superconductivity “

What answers are given in the video to these questions?
1 How does being cold help?

electrons/ get together/ easy/ move around/in pairs

2 So what makes superconductors ‘super’?

move around/ easy/regular conductors/

3 Why is it important to get rid of vortices? (vortex, pl .vortices-вихрь)

easy/ move/ big vortices/ get rid/ move faster/

4 What are scientists trying to do in order to solve this problem?

build/ tiny cages/ trap/ tornadoes/ improve/ efficiency of electricity/



9 Match English words and phrases with Russian equivalents.
BCS theory, the Meissner effect, the division of superconductors into the two categories,

mercury, in subsequent decades, to expel magnetic fields, refrigerant, a thin layer of insulator, macroscopic properties of superconductors, finally, wire, discover, superfluid.


ртуть, охладитель, в последующие десятилетия, вытеснять магнитное поле, эффект Мейснера, макроскопические свойства сверхпроводников, разделение сверхпроводников на два рода, БКШ теория, тонкий слой диэлектрика, наконец, открывать (обнаруживать), провод, сверхтекучесть.


10 Read the text and answer the questions.
1 Who discovered superconductivity?

2 Who made further advances in the field of superconductivity?

3 What did the BCS theory explain?

4 Who developed the first superconducting wire?



Useful notes

Нeike Kamerlingh Onnes- голландский физик и химик Хейке Камерлинг Оннес

liquid helium-жидкий гелий

lead |lеd| -свинец

niobium nitride |naɪˈoʊbiəm|-нитрид ниобия

expel-вытеснять, выталкивать

Walter Meissner and Robert Ochsenfeld- немецкие физики Вальтер Мейснер и Роберт Оксенфельд

F.and H. London- немецкие физики-теоретики Фриц и Хайнц Лондоны

John Bardeen, Leon Cooper and John Schrieffer- американские физики Джон Бардин, Леон Купер, Джон Роберт Шриффер.

BCS theory- БКШ теория

phonon- фонон (квант колебательной энергии кристаллической решётки)

niobium-titanium alloy |naɪˈoʊbiəm tɪˈteɪniəm ˈælɔɪ| -сплав из титана и ниобия

Type I and Type II superconductors – сверхпроводники I и II рода

Brian Josephson – английский физик Брайан Джозефсон

Paul Chu – американский физик китайского происхождения Пол Чу

lanthanum |ˈlænθənəm| – химический элемент лантан (La)

yttrium |ˈɪtriəm| – химический элемент иттрий (Y)
History of superconductivity

Superconductivity was discovered in 1911 by Heike Kamerlingh Onnes, who was studying the resistance of solid mercury at cryogenic temperatures using the recently discovered liquid helium as a refrigerant. At the temperature of 4.2 K, he observed that the resistance abruptly disappeared. For this discovery, he was awarded the Nobel Prize in Physics in 1913.

In subsequent decades, superconductivity was found in several other materials. In 1913, lead was found to be superconductive at 7 K, and in 1941 niobium nitride was found to be superconductive at 16 K.

The next important step in understanding superconductivity occurred in 1933, when Walter Meissner and Robert Ochsenfeld discovered that superconductors expelled applied magnetic

fields, a phenomenon that has come to be known as the "Meissner effect." In 1935 F. and H. London showed that the Meissner effect was a consequence of the minimization of the electromagnetic free energy carried by superconducting current.

In 1950 Lev Landau and Vitalij Ginzburg formulated what came to be called the phenomenological Ginzburg-Landau theory of superconductivity. This theory had great success in explaining the macroscopic properties of superconductors. In particular, Alexei Abrikosov showed that the theory predicts the division of superconductors into the two categories, now referred to as Type I and Type II. Abrikosov and Ginzburg were awarded the 2003 Nobel Prize for their work (Landau having died in 1968).

The complete, microscopic theory of superconductivity was finally proposed in 1957 by John Bardeen, Leon Cooper, and John Schrieffer. It came to be known as the BCS theory. Superconductivity was independently explained by Nikolay Bogolyubov . The BCS theory explained the superconducting current as a superfluid of "Cooper pairs"—pairs of electrons interacting through the exchange of phonons. For this work, the authors were awarded the Nobel Prize in 1972. In 1959 Lev Gor'kov showed that the BCS theory becomes equivalent to the Ginzburg-Landau theory close to the critical temperature.

In 1962 the first commercial superconducting wire, a niobium-titanium alloy, was developed by researchers at Westinghouse Electric Corporation. In the same year, Brian Josephson made the important theoretical prediction that a supercurrent can flow between two pieces of superconductor separated by a thin layer of insulator. This phenomenon, now called the "Josephson effect," is exploited by superconducting devices such as SQUIDs (superconducting quantum interference devices). Josephson was awarded the Nobel Prize for this work in 1973.

Until 1986, physicists had believed that the BCS theory forbade superconductivity at temperatures above about 30 K. But that year it was found by Paul C. W. Chu of the University of Houston that replacing the lanthanum with yttrium raised the critical temperature to 92 K. This latter discovery was significant because liquid nitrogen could then be used as a refrigerant (the boiling point of nitrogen is 77 K). This is important commercially because liquid nitrogen can be produced cheaply on-site with no raw materials.Many other superconductors have since been discovered, and the theory of superconductivity in these materials is one of the major outstanding challenges of theoretical condensed matter physics
11 Match the sentence halves.
1Superconductivity was discovered in 1911 a) when Meissner discovered that

by K. Onnes superconductors expelled applied magnetic fields

2The next important step in understanding b) pairs of electrons interacting through the

superconductivity occurred in 1933 exchange of phonons

3 In 1950 Landau and Ginzburg formulated c) who was studying the resistance of solid

what came to be called mercury at cryogenic temperatures

4 The complete, microscopic theory of d) can flow between two pieces of superconductor

superconductivity was finally proposed separated by a thin layer of insulator

5 The BCS theory explained the e) the phenomenological Ginzburg-Landau

superconducting current as a superfluid theory of superconductivity

of ‘Cooper pars’-

6 In 1962 Brian Josephson made the f) in 1957 by Bardeen, Cooper, and Schrieffer

important theoretical prediction that

suprcurrent




12 Read the text again. Are the statements true, false or is the information not given?

1 Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic fields occurring in certain materials when cooled below a characteristic critical temperature.

2 The occurrence of the Meissner effect indicates that superconductivity cannot be understood simply as the idealization of perfect conductivity in classical physics.

3 In a superconductor, the resistance drops gradually to zero when the material is cooled below its critical temperature.

4 In 1986 it was discovered that some ceramic materials have a critical temperature above 90 K

5 In ordinary conductors, such as copper and silver, the decrease of temperature is limited by impurities and other defects

6 A superconductor is generally considered high temperature if it reaches a superconducting state when cooled using liquid nitrogen or low temperature if more aggressive cooling techniques are required to reach its critical temperature.

7 Liquid nitrogen boils at 77 K, and superconductivity at higher temperatures than this facilitates many experiments and applications that are less practical at lower temperatures.

8 The electrical resistance of a metallic conductor decreases gradually as temperature is lowered
13 Summarize the text to the class.

Use these dates as a plan.
1911 1933 1950 1957 1962 1986

Study the table
Complex Object
Подлежащее + Сказуемое + Дополнение + Infinitive

глагол – характеристика переводится подлежащим переводится


Active сказуемым

дают главное предложение придаточного предложения




  1. We want them to come to see us tomorrow.

Мы хотим, чтобы они завтра пришли к нам.

  1. We expected the delegation to come in time.

Мы ожидали, что делегация приедет во время.

  1. I know her to work at this problem.

Я знаю, что она работает над этой проблемой.


For more information see Grammar Reference on page 26
14 Find Complex Object in the sentences below.
1 We know the scientist to study this proposal thoroughly.

2 I suppose him to come tonight.

3 She told me to win the competition.

4 I want you to translate this text in an hour.

5 Do you want him to increase the pressure in the system?

6 We thought her to be still sleeping.

7 They expect them to control the electrical pressure in the circuit.

8 Mum warned her baby not to touch the socket.


15 Put the words in the correct order to make sentences.
1 She/ him/ the contacts/ wanted/ of the circuit/ to connect

2 parents/ like/ My/ an engineer/ me/ would/ to become

3 books/ us/ her/ She/ to borrow/ allowed

4 expect/ to phone/ I/ her

5 this/ I/ to remember/ you/ want/ rule

6 a good/ They/ him/ friend/ think/ to be

7 friend/ me/ to help/ My/ wants/ him

8 We/ to be late/ him/ expected


16 Correct the mistake in each sentence.
1 Peter was asked test the equipment.

2 The teacher told the students to not use a broken device.

3 New data let us to carry out another experiment.

4 His discovery allowed an invention be made.

5 This analysis permitted them obtain new data.

6 The lecturer would like us complete the work on time.

7 Glasses make him to look older.

8 I offered her go home.


17 Translate the sentences into English.
1 Я хочу, чтобы вы прочли эту статью.

2 Она хотела, чтобы друзья остались.

3 Вам бы хотелось, чтобы они рассказали правду?

4 Преподаватели хотят, чтобы студенты сдали экзамены.

5 Мне не хотелось, чтобы она знала об этом.

6 Хотите я дам вам мой словарь?

7 Мои родители хотели, чтобы я поехал с ними.

8 Мне не хочется, чтобы вы опаздывали на занятия.



18 Make up a story about Jane Mitchell with a given situation, using Complex Object

construction.

Jane Mitchel studies at a London Secretarial College. She is a long way from home. Her family wants her to do a lot of things.

For example:

Model: - a good specialist



They (the family) want Jane to become a good specialist.
Good marks in her tests, a letter home every week, eat regularly, with good family in London, home for holiday, her birthday with her new friends, a new warm coat, to write about her new friends, a good job later.





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