- •Negative (with no auxiliary verb)
- •Questions (with the auxiliary verb)
- •Questions (with no auxiliary verb)
- •Read and translate the following international words:
- •Consult the table above and write full sentences. Use is/are. Where possible change sentences to use isn’t/aren’t.
- •Complete the sentences using the following verbs: emit(s), occur(s), flow(s), define(s), repel(s), attract(s), have(has).
- •Put the verb in brackets into the correct form. Insert always/never/
- •Mind the word-order and compile sentences from the following words:
- •Put questions to the following sentences:
- •Form nouns from the following verbs using the suffix –tion and translate them:
- •Guess the meaning of the following adjectives paying attention to the suffix – ic:
- •Read and translate word-combinations
- •Choose as many words from the table оf ex. 1 as you can and form sensible sentences in Present Simple (affirmative, negative and interrogative).
- •Specialist reading
- •Mark the following sentences as true (t) or false (f). Then read the text “Diodes” and check yourself.
- •Read the text again and complete the sentences with the correct ending.
- •Work in pairs. Ask your partner questions based on the text. Make sure you use correct auxiliary verb.
- •Speaking
- •In Russian write a content-based summary of the text you have translated.
- •Make a reverse written translation (from Russian into English) of your summary.
- •Find more information about conduction of current in a semiconductor diode and tell your group mates.
- •Negative
- •Adjectives and adverbs
- •Degrees of Comparison
- •Fill in the table.
- •Put the verb in brackets into the correct form, Present Continuous or Present Simple.
- •Choose the appropriate English equivalents:
- •Translate the following sentences. Mind the meaning of the highlighted words.
- •Choose as many words from the table оf ex. 1 as you can and form sensible sentences in Present Continuous (affirmative, negative and interrogative).
- •Specialist reading
- •Read the text “Triodes” and choose its best summary.
- •15. Read the text again and complete the sentences.
- •Speaking
- •Forms of the Personal Pronouns and One
- •Fill in the table.
- •Read and translate the following international words:
- •Choose the appropriate English equivalents. What do all of them have in common?
- •Translate starting from the first component:
- •Give the three forms of the following irregular verbs.
- •Choose the appropriate English equivalents:
- •Choose the appropriate Russian equivalents to Participles II:
- •Do not translate! Define where the subject is the doer of the action.
- •Translate paying attention to the Passive Voice.
- •Make up sentences from the following words. Put a in the Present Simple Passive, b – in the Present Continuous Passive.
- •Make questions to match the answers. All of them are in the Passive Voice.
- •Match the following sentences with their translations. Which of them are in Passive?
- •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).
- •Match the terms in Table a with their definitions in Table b
- •Translate paying attention to the meanings of the word one.
- •Change the form of the personal pronouns given in brackets.
- •Make up sentences with personal pronouns on the topic of electronics and physics. Specialist reading
- •Read the text again and complete the sentences with the correct beginning or ending.
- •Work in pairs. Ask your partner questions based on the text. Make sure you use correct auxiliary verb.
- •Speaking
- •Conductivity
- •In Russian write a content-based summary of the text you have translated.
- •Make a reverse written translation (from Russian into English) of your summary.
- •Find more information about classification of materials based on other principles and tell your group mates.
- •Negative (with the auxiliary verb)
- •Negative (with no auxiliary verb)
- •Questions (with the auxiliary verb)
- •Questions (with no auxiliary verb)
- •1. Fill in the table.
- •4. Put in the missing words, using the words from the previous units and the table above.
- •5. Put all possible questions to the following statements.
- •6. Put the verb in brackets into the Past Simple.
- •7. Form nouns from the following adjectives using the suffix -ity and translate them:
- •8. Choose the appropriate English equivalents:
- •11. Match the following word-combinations with their translations.
- •12. Match the following sentences with their translations.
- •13. Choose as many words from the table оf ex. 1 as you can and form sensible sentences in Past Simple (affirmative, negative and interrogative).
- •Specialist reading
- •Matter, Elements and Atoms
- •Read the text again and complete the sentences.
- •16. Match the terms in Table a with their definitions in Table b.
- •Speaking
- •18. You are taking your exam in Physics. Your examination card says: Matter, its definition and basic notions. Your partner is your examiner. Answer his questions and try to get a good mark.
- •19. Divide into 2 groups. Group 1 translates Extract a and group 2 – extract b of the text “Electricity” with a dictionary in writing, paying attention to the use of the Past Simple.
- •3. Read the dialogue and learn how to speak about your past activities. Put the verb in brackets into the Past Continuous. Pay attention to the terms of electricity.
- •4. Put in the missing words, using the words from the table above:
- •5. Put all possible questions to the following statements.
- •6. Put the verb in brackets into the Past Continuous.
- •7. Form nouns from the following verbs using the suffix -ment and translate them:
- •8. Choose the appropriate English equivalents.
- •9. Translate the text. Use a dictionary if necessary. To each sentence put different type of question in Present Continuous.
- •11. Match the following word-combinations with their translation.
- •12. Match the following sentences with their translation.
- •13. Choose as many words as you can of ex.1 and form sensible sentences.
- •Specialist reading
- •14. Read the text “Covalent Bonds” only once. How much can you remember? Answer these questions without additional reading.
- •If you failed try to answer these questions again after doing the exercises given below the text.
- •15. Read the text again and complete the sentences.
- •16. Study the text and translate the following:
- •17. Match the terms in Table a with their definitions in Table b.
- •Speaking
- •18. Summarize the text “Covalent Bonds” in 150 words.
- •19. In pairs ask and answer text-based questions.
- •20. Divide into 2 groups. Group 1 translates Extract a and group 2 – extract b of the text “Semiconductors” with a dictionary in writing.
- •Past Continuous Passive Affirmative
- •Negative
- •1. Fill in the table.
- •2. Read and translate the following international words:
- •3. Put in the missing words, using the words from the table above:
- •4. Put all possible questions to the following statements.
- •5. Put the verb in brackets into the Past Simple Passive.
- •6. Change the following sentences so as to use the Past Simple Passive.
- •7. Form nouns from the following verbs and translate them:
- •9. Match the following words and phrases with their translation.
- •10. Choose the nouns from the following words.
- •11. Match the following expressions with their translation:
- •12. Choose as many words from the table оf ex. 1 as you can and form sensible sentences in Past Simple Passive or Past Continuous Passive (affirmative, negative and interrogative).
- •Specialist reading
- •13. Read the text “Electrons and Holes” only once. How much can you remember? Answer these questions without additional reading.
- •If you failed try to answer these questions again after doing the exercises given below the text.
- •14. Read the text again and complete the sentences.
- •15. Match the terms in Table a with their definitions in Table b.
- •Speaking
- •17. In pairs ask and answer text-based questions.
- •18. Divide into 2 groups. Group 1 translates Extract a and group 2 – Extract b of the text “Supernovae” with a dictionary in writing.
- •Unit VII
- •Language Work Present Perfect Active (I have patented)
- •Present Perfect Passive (measurements have been done)
- •Fill in the table.
- •Fill in the gaps using the following verbs: break, free, move, come, occur, appear.
- •Make up sentences using Present Perfect. Use the prompts in brackets. Mind the position of just/already/yet.
- •Open the brackets and complete the dialogues with just, already, yet. Use Passive Voice where nessesary.
- •You are asking students questions about things they have done. Make questions with ever using the words in brackets.
- •Read the situations and write sentences using the example.
- •Rewrite these sentences into Passive Voice.
- •Make sentences from the words in brackets using the Present Perfect Passive.
- •Form adjectives from the following nouns using the suffix -ous and translate them.
- •Read and translate word-combinations.
- •Match the following sentences with their translations.
- •Choose as many words from the table of ex.1 as you can and form sensible sentences.
- •Specialist reading
- •Read the text “The Movement of Holes”. Mark the following sentences as true (t) or false (f).
- •The Movement of Holes
- •Read the text again and complete the sentences with the correct ending.
- •Work in pairs. Ask your partner some questions based on the text. Make sure you use the correct auxiliary verb.
- •Speaking
- •Measuring the Movement of Holes in Crystal Surfaces
- •In Russian write a content-based summary of the text you have translated.
- •Make a reverse written translation (from Russian into English) of the text “Measuring the Movement of Holes in Crystal Surfaces”.
- •Serve as simultaneous interpreter. Make an oral reverse interpretation of the text. Unit VIII
- •Language Work Past Perfect Active (I had measured)
- •Past Perfect Passive (it had been measured) Affirmative
- •Questions
- •Open the brackets and put the verbs into the Past Perfect or Past Indefinite/Continuous Tense(Active or Passive).
- •Make the sentences of ex.2 negative and interrogative.
- •For each situation, write a sentence ending with never … before. Use the verbs in brackets.
- •Put the verb into the correct form, Past Perfect (I had measured) or Past Simple (I measured).
- •Complete these sentences with the following verbs (in the form of Past Perfect Passive):change, know, analyze, use, install.
- •Rewrite these sentences into Past Perfect Passive/Active.
- •Match the following sentences with their translations.
- •Specialist reading
- •Read the text “Silicon”. Find the answers to the following questions.
- •Silicon
- •Read the text again and select the best completion for each sentence. Complete the following sentences using the multiple choice suggested. There might be more than one variant.
- •Complete the sentences with the correct ending according to the text.
- •Speaking
- •Summarize the text “Silicon” in 150 words.
- •Translate the text “Applications of Silicon” paying attention to new technical terms in writing. Applications of Silicon
- •In Russian write a content-based summary of the text you have translated.
- •Make a reverse written translation (from Russian into English) of your summary.
- •Find more information about silicon applications and tell your group mates.
Choose as many words from the table оf ex. 1 as you can and form sensible sentences in Present Continuous (affirmative, negative and interrogative).
For example: In Fig. A the grid is controlling the current flow.
Specialist reading
Read the text “Triodes” and choose its best summary.
The electron flow in a triode.
The influence of the grid on the electron flow.
The structure of a triode, basic principles of its operation and functions.
In a vacuum-tube triode there are three electrodes: a cathode, a plate and a grid. When heated the cathode emits electrons. Electrons flow from the cathode to the plate. The grid is placed between the cathode and the plate. It controls the flow of electrons. The closer the grid is to the cathode, the more influence it has on the electron flow. Even if a small negative voltage is applied to the grid, this results in a large plate current. If a large negative voltage is applied to the grid, the plate current decreases. For example, the plate voltage is 150 volts. A small negative voltage of 10 volts is applied to the grid. This results in a current flow of 20 m. a. But if the negative voltage on the grid is decreased to 8 volts, this will result in a current of 30 m.a. Due to this property of a triode, it can be used for amplification.
15. Read the text again and complete the sentences.
In a vacuum-tube triode there are…
When heated…
Electrons flow…
The grid is placed…
… the flow of electrons.
The closer the grid is to the cathode …
… this results in a large plate current.
If a large negative voltage is applied to the grid …
… it can be used for amplification.
Match the terms in Table A with their definitions in Table B
Table A |
Table B |
|
|
Speaking
16. Work in pairs. Draw a circuit of a triode and ask your partner some questions based on it. Make sure all the questions and answers are in Present Continuous.
For example:
Student A – In what direction are the electrons shown in the scheme moving?
Student B – They are moving towards the plate.
17. Summarize the text “Triodes” in 150 words using the following plan:
The structure of a vacuum-tube triode.
The principles of its work.
The function of a grid.
The influence of the distance between the cathode and the grid on the electron flow.
The influence of the voltage on the current flow.
The grid application.
Compare a vacuum-tube triode with a diode using appropriate degrees of comparison and the following words of comparison and contrast: both, like, whereas, unlike, but, however.
For example: 1. When heated in both tubes cathodes emit electrons.
2. A triode can be used for amplification unlike a diode which is used as …
Act as an interpreter. Translate the description of the operation of a semiconductor triode given by your group mates from Russian into English.
Divide into 2 groups. Group 1 translates Extract A and group 2 – extract B of the text “Heat Transfer and Appearance of Tubes” with a dictionary in writing.
Highlighted words are international. Try to guess their meaning without a dictionary.
Extract A
Any types of vacuum tubes can be recognized from their appearance. A considerable amount of heat is produced when tubes operate. In most circuits the tube is about 30-60% efficient depending on the class of operation (classes A, B, or C), which means that 40-70 % of input power is lost as heat. The requirements for heat removal significantly change the appearance of high-power vacuum tubes.
Most tubes contain two sources of heat when operating. The first one is the filament or heater. Some types contain a directly heated cathode. This is a filament similar to an incandescent electric lamp and some types glow brightly like a lamp, but most glow dimly. (The "bright emitter" type possesses a tungsten filament alloyed with 1-3 % thorium which reduces the work function of the metal, giving it the ability to emit sufficient number of electrons at about 2000 degrees Celsius. The "dull emitter" types also possess a tungsten filament but it is coated by a mixture of calcium, strontium and barium oxides, which emit electrons easily at much lower temperatures due to a monolayer of mixed alkali earth metals coating the tungsten when the cathode is heated to about 800-1000 degrees Celsius.)
The second form of cathode is the indirectly heated form which usually consists of a nickel tube, coated on the outside with the same strontium, calcium, barium oxide mix used in the "dull emitter" directly heated types, and fitted with a tungsten filament inside the tube to heat it. This tungsten filament is usually uncoiled and coated by a layer of alumina, (aluminium oxide), to insulate it from the nickel tube of the actual cathode. This form of construction allows for a much greater electron emitting area and, because the heater is insulated from the cathode, the cathode can be positioned in a circuit at up to 150 volts more positive than the heater or 50 volts more negative than the heater for most common types. It also allows all the heaters to be simply wired in series or paralleled rather than some requiring special isolated power supplies such as specially insulated windings on power transformers or separate batteries.
Extract B
For small-signal tubes such as used in radio receivers, heaters are rated from 50 mW to 5 watts, (directly heated), and about 500 mW to 8 watts for indirectly heated types. Once filament/heater power is included in total power consumption, small tubes have very poor efficiencies. A 6BM8/ECL82 audio stage consumes a total power of some 15 watts for 3.5 watts of useful audio power, giving an efficiency of around 23%. Some signal amplifiers, particularly high-frequency amplifiers such as the 6BA6, consume some 5.9 watts of power in normal operation and deliver only 1.1 watts of power at the plate.
The second source of heat is generated at the anode, when electrons, accelerated by the voltage applied to the anode, strike the anode and impart a considerable fraction of their energy to it, raising its temperature. In tubes used in power amplifying or transmitting circuits, this source of heat will exceed the power dissipated in the cathode heater. (The plates or anodes of 6L6 devices used in guitar amplifiers can sometimes be seen to reach red heat if the bias is set too high, they should not emit any visible radiation when driven at maximum ratings.) No tubes in domestic, music, or studio equipment should operate with glowing anodes.
This heat usually escapes the device by (black body) radiation from the anode/plate as infra red light. Some is conducted away through the connecting wires going to the base but none is convected in most types of tube because of the vacuum and the absence of any gas inside the bulb to convect.
For devices required to radiate more than 500 mW or so, usually indirectly heated cathode types, the anode or plate is often treated to make its surface less shiny, (see black body radiator), and to make it darker, either gray or black. This helps it radiate the generated heat and maintain the anode or plate at a temperature significantly lower than the cathode, a requirement for proper operation.
Other internal elements of high-power tubes, such as control grids and screen grids, may also dissipate heat if carrying large currents. Limits to grid dissipation are listed for such devices to prevent distortion and failure of the grids.
In Russian write a content-based summary of the text you have translated.
Translate into English the summary made in ex.21 of the text you haven’t read.
Make a reverse written translation (from Russian into English) of the Extract you have translated.
Serve as simultaneous interpreter. Make an oral reverse interpretation of the text.
Find more information about vacuum tubes and tell your group mates.
UNIT III
CONDUCTIVITY |
Language Work
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
|
[t] |
placed, developed |
-ed |
[d] |
used, described |
|
[Id] |
heated, translated |