Present Simple Passive

am/is/are + done/attracted (past participle)

Active: We call such materials conductors.

Passive: Such materials are called conductors.

They are not called insulators.

When is a negative voltage applied to the plate?

Present Continuous Passive

am/is/are being + done/considered(past participle)

Active: Look! The student is placing the grid between the cathode and anode.

Passive: Look! The grid is being placed between the cathode and anode by the student.

This figure shows that a voltage is not being applied to the grid at the moment.

Is the circuit being completed while providing the experiment?

Reading

Forms of the Personal Pronouns and One

1. Fill in the table.

2. Read and translate the following international words:

Nouns (n): aluminium, atom, computer, dielectric, discussion, generator, germanium, industry, kilowatt, machine, robot, rotor, selenium, steel, structure, temperature, test, turbo-generator.

Adjectives (adj): cryogenic, monolythic, proportional.

Verbs (v): circulate, class, classify, discuss, generate, test.

3.Choose the appropriate English equivalents. What do all of them have in common?

притяжение – 1. attraction; 2. attractive; 3. attracted

описание – 1. describe; 2. description; 3. described

нагревание – 1. heater; 2. heating; 3. heat

работа – 1. operator; 2. operate; 3. operation

определение – 1. defined; 2. define; 3. definition

проводник – 1. conductor; 2. conductivity; 3. conducted

направление – 1. direct; 2. direction; 3. directly

выпрямление – 1. rectifier; 2. rectified; 3. rectification

изоляция – 1. insulator; 2. insulated; 3. insulation

эмиссия 1. emission; 2. emit; 3. emitted

4. Form adverbs from the following adjectives using the suffix -lу and translate them:

For example: absolute — абсолютный; absolutely — абсолютно

comparative — сравнительный;

direct — прямой;

easy — легкий;

normal — нормальный;

practical — практический;

relative — относительный;

usual — обычный.

5. Form adjectives from the following nouns using the suffix -1ess and translate them:

For example: motion — движение; motionless — неподвижный.

limit — предел;

wire — проволока;

use — польза;

form — форма;

water — вода;

power — сила, энергия;

time — время.

What’s the meaning of this suffix?

6. Translate starting from the first component:

7. Read the following. Why are these verbs divided into three groups?

8. Give the three forms of the following irregular verbs.

For example: know – knew – known

be – …; have – …; give – … ; show – …; see – …; take – …

Find more in a dictionary and learn them.

9.Choose the appropriate English equivalents:

известный —1. knew; 2. known; 3. know

показанный—1. show; 2. showed; 3. shown

увиденный— 1. see; 2. seen; 3. saw

помещенный — 1. place; 2. placing; 3. placed

изолированный— 1. insulate; 2. insulated; 3. insulating

данный — 1. give; 2. given; З. gave

взятый— 1. take; 2. took; 3. taken

названный — 1. called; 2. calling; 3. call

использованный — 1. using; 2. use; 3. used

10. Choose the appropriate Russian equivalents to Participles II:

A.1. compared; 2. defined; 3. shown; 4. obtained; 5. decreased; 6. described; 7. called

1. показанный; 2. полученный; 3. описанный; 4. сравниваемый; 5. названный; 6.уменьшенный; 7. определенный

B.1. increased; 2. placed; 3. taken; 4. known; 5. amplified; 6. given; 7. switched on

1. помещенный; 2. известный; 3. данный; 4. включенный; 5. увеличенный; 6. усиленный; 7. взятый

11.Do not translate! Define where the subject is the doer of the action.

1. a) The grid controls the flow of electrons. – b) The grid is placed between the cathode and anode.

2. a) A large negative voltage is applied to the grid. – b) We do not apply a large positive voltage to the grid.

3. a) Transistors are used in this function. – b) We use transistors for amplification.

4. a) New devices are being installed here at the moment. – b) They are installing new devices here now.

5. a) The charged particles inside the material can be set in motion. - b) We can set the charged particles inside the material in motion.

6. a) Physicists classify materials according to their electrical properties. – b) Materials can be classified according to their electrical properties.

7. a) Classification is based on the ability of a material to conduct electricity. - b) We base our classification on the number of charged particles.

8. a) Metals, for example, having many free electrons, can readily conduct current at room temperature. – b) Look at this device! Current is being conducted.

How does the use of the Passive Voice depend on the doer of the action?

12. Translate paying attention to the Passive Voice.

1. Materials can be classified according to their electrical properties. 2. This method is based on the ability of a material to conduct electricity. 3. What materials are called conductors? 4. The materials that have very few or no free electrons are called insulators. 5. Electronics is defined in an English dictionary as "the study of conduction of electricity in a vacuum, in gases and in semiconductors". 6. When the cathode is heated, it emits electrons. 7. The electrons are repelled toward the plate by the negative voltage on the cathode. 8. If a negative voltage is applied to the plate, current does not flow.

13. Make up sentences from the following words. Put A in the Present Simple Passive, B – in the Present Continuous Passive.

A.

1. the/electrons/not/ attract/by/the/negative/voltage/on/the/ plate.

2. materials/classify/according/to/their/chemical/properties.

3. particles/can/set/in/motion?

4. not/on/it/ability/of/electricity/a/material/the/to/conduct/base.

5. flow/by/electrons/the/control/a/of/grid.

6. use/as/grids/amplifiers?

7. the/between/grid/place/the/cathode/and/the/plate.

8. not/such/call/semiconductors/materials.

9. the/more/the/better/you/will/words/translate/from/English/know/into/

Russian/you.

10. the/of/how/electrons/control/flow?

11. nowadays/the/losses/of/lighting/power/compensate/by/a/mirror/reflector.

12. conductors/materials/what/call?

B.

1. the/cathode/heat/by/the/heater.

2. the/current/make/to/flow/through/the/tube.

3. by/electrons/emit/cathode/the.

4. plate/the/current/decrease.

5. repel/the/toward/electrons/the/plate.

6. define/by/electronics/the/physicist.

7. to/voltage/a/negative/apply/the/plate.

8. of/electrons/the/describe/by/the/flow/student.

9. of/fundamentals/electronics/the/discuss.

10. semiconductors/and/and/insulators/consider/now/conductors.

14. Make questions to match the answers. All of them are in the Passive Voice.

For example:

Q – What is being discussed in the lecture room now?

A – The classification of materials is being discussed in the lecture room now.

1. Q – How …

A –Materials can be classified in many ways.

2. Q – What …

A – One of the ways is based on the ability of a material to conduct electricity.

3. Q – What particles …

A – Only charged particles inside the material can be set in motion.

4. Q – How …

A – Such materials are called conductors.

5. Q – Is …

A – The flow of electrons is being controlled.

6. Q – When …

A – The fundamentals of electronics are being discussed now.

7. Q – Who … by

A – The flow of electrons is being described by the student.

8. Q – What … with

A – The conductivity is being amplified with a number of new devices.

15. Match the following sentences with their translations. Which of them are in Passive?

16. Choose as many words from the table оf ex. 1 as you can and form sensible sentences in Present Simple Passive and Present Continuous Passive (affirmative, negative and interrogative).

For example: The number of particles is unlimited.

17. Match the terms in Table A with their definitions in Table B

18. Translate paying attention to the meanings of the word one.

For example: There are many ways of classifying materials. The one we shall speak about is based on the ability of a material to conduct electricity. – Существует много способов классификации материалов. Тот (способ), о котором мы будем говорить, основан на способности материала проводить электричество.

1. There are many types of robots; the ones, we are going to discuss today, are the robots of the 3-rd gen­eration.

2. The new computer is more powerful than the one put into service last year.

3. That semiconductor device is more efficient than the one under consideration.

4. Which of the gadgets is more useful than the new one?

5. There can be many schemes of different devices; the one given in Unit 2 shows the electron flow in a vacuum tube.

19. Change the form of the personal pronouns given in brackets.

For example: Physicists should work in order to realize (they) ambitions. - Physicists should work in order to realize their ambitions.

1. Today we shall speak about classifying materials according to (they) electrical properties.

2. There are many ways of classifying (they).

3. The one we shall speak about is based on (it) ability to conduct electricity.

4. Do only electrons take part in (it)?

5. Сonductivity is the result of the motion of (they).

6. It is directly proportional to the number of (they) inside the material that can be set in motion.

7. There are materials which have very few of (they).

8. Materials are classified according to (they) properties.

9. Many of (they) were discussed in the lab.

10. (It) number is not relevant.

11. The scientist (he) proved the results to be correct. He didn’t need help of any other staff.

12. (We) results in accomplishing this project were phenomenal.

13. These experiments were (they).

20. Make up sentences with personal pronouns on the topic of electronics and physics.

SPECIALIST READING

21. Read the text “Classifying Materials” and fill in the table.

There are many ways of classifying materials. The one we shall use here is based on the ability of a material to conduct electricity. It is known that conduction takes place as a result of the motion of charged particles, usually electrons. The ability of any material to conduct electricity is directly proportional to the number of charged particles inside the material that can be set in motion. Materials (for example metals) that have relatively large numbers of free electrons readily conduct electric current and are called conductors. Other materials having very few (or no) free electrons do not readily conduct electric current under normal conditions and are called insulators. Such materials as selenium, silicon and germanium have more free electrons than insulators, but fewer than conductors. They are called semiconductors. Conductivity depends on temperature. In metals the higher the temperature, the lower the conductivity. But in semiconductors, if the temperature rises, the conductivity increases but within certain limits. It should be realized¹ that the terms “conductor” and “insulator” are not absolute, that is² some conductors do not conduct as well as other conductors, while some insulators do not insulate as well as other insulators.

¹ it should be realized – следует учесть ² that is – то есть

22. Read the text again and complete the sentences with the correct beginning or ending.

1. … based on the ability of a material to conduct electricity.

2. Conduction takes place as …

3. The ability of any material to conduct electricity …

4. … are called conductors.

5. Materials having very few (or no) free electrons …

6. Semiconductors are materials …

7. The terms “conductor” and “insulator” are not absolute, that is …

23. Work in pairs. Ask your partner questions based on the text. Make sure you use correct auxiliary verb.

1. Ways of classifying materials (How many?) …

2. The ability to conduct electricity (What?) …

3. As a result of (What?) …

4. Is directly proportional to (General question) …

5. Under normal conditions (Under what conditions?) …

6. Readily conduct electric current (How?) …

7. Such materials as selenium, silicon and germanium (How?) …

8. It should be realized (What?) …

24. Answer the following questions.

1. What is conduction?

2. What is conduction based on?

3. What groups are materials classified into according to their conductivity?

4. How does conductivity depend on temperature?

5. What materials are called: a) conductors, b) semiconductors, c) insulators?

SPEAKING

25. In groups finish the map based on the text “Classifying Materials” and use it while summarizing the text in 150 words.

Conductivity

26. You are at an international conference. Act as interpreters. Student A translates the description of the classification of materials made by his group mates from English into Russian and student B makes a reverse translation.

27. Translate the text “Energy Bands and Electrical Conduction” with a dictionary in writing paying attention to the use of the Passive Voice.

Electrons in semiconductors can have energies only within certain bands (i.e. ranges of levels of energy) between the energy of the ground state, corresponding to electrons which are tightly bounded to the atomic nuclei of the material, and the free electron energy, which is required for an electron to escape entirely from the material. Each energy band corresponds to a large number of discrete quantum states of electrons, and most of the states with low energy (closer to the nucleus) are full, up to a particular band. This one is called the valence band. Semiconductors and insulators are distinguished from metals because the valence band in semiconductor materials is nearly filled under normal operating conditions, thus causing more electrons to be available in the "conduction band," which is the one immediately above the valence band.

The ease with which electrons in a semiconductor can be excited from the valence band to the conduction one depends on the band gap between them, and it is the size of this energy band gap that serves as an arbitrary dividing line (roughly 4 eV) between semiconductors and insulators.

In the context of covalent bonds, an electron moves by hopping to a neighboring bond. According to the Pauli Exclusion Principle it has to be lifted into the higher anti-bonding state of that bond. In the context of delocalized states, for example in one dimension – that is in a nano wire, for every energy there is a state with electrons flowing in one direction and one state for the electrons flowing in the other. For a net current to flow some more states for one direction than for the other direction have to be occupied and for this energy is needed; in the semiconductor the next higher states lay above the band gap. Often this is stated as: full bands do not contribute to the electrical conductivity. However, as the temperature of a semiconductor rises above absolute zero, there is more energy in the semiconductor to spend on lattice vibration and – more importantly for us – on lifting some electrons into the energy states of the conduction band. The current-carrying electrons in the conduction band are known as "free electrons", although they are often simply called "electrons" if context allows this usage to be clear.

Electrons excited to the conduction band also leave behind them electron holes, or unoccupied states in the valence band. Both the conduction band electrons and the valence band holes contribute to electrical conductivity. The holes themselves don't actually move, but a neighboring electron can move to fill the hole, leaving a hole at the place it has just come from, and in this way the holes appear to move, and the holes behave as if they were positively charged particles.

One covalent bond between neighboring atoms in the solid is ten times stronger than the binding of the single electron to the atom, so freeing the electron does not imply destruction of the crystal structure.

28. In Russian write a content-based summary of the text you have translated.

29. Make a reverse written translation (from Russian into English) of your summary.

30. Find more information about classification of materials based on other principles and tell your group mates.

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