· Diodes permit current to flow in only one direction.
· The dictionary defines electronics as the study of conduction of electricity.
-es after -s / -sh / -ch: pass – passes, finish – finishes, watch – watches
-y – -ies: study – studies, rectify – rectifies
also: do – does, go – goes
· Diodes have 2 basic elements.
· Every diode has a cathode and a plate.
Negative (with the auxiliary verb)
|I/we/you/they he/she/it||don't doesn't||amplify/define/direct|
· Diodes don’t permit current to flow in opposite directions.
· Positive voltage on the plate doesn’t repel electrons.
Negative (with no auxiliary verb)
|I/we/you/they/ he/she/it||can/ may/must||not||amplify/define/ direct|
|I/we/you/they/ he/she/it||am/is/are||not||a physicist(s)|
|I/we/you/they/ he/she/it||have/has||no/hasn’t or don’t/doesn’t have||a heater|
· These devices can’t be amplifiers.
· They are not physicists.
· This gadget doesn’t have a/has no heater.
Remember:There is no grid in a diode. But: There isn’t a grid in a diode.
A diode has no grid. A diode hasn’t a grid.
Questions (with the auxiliary verb)
|Do Does||I/we/you/they he/she/it||amplify/define /direct?|
· Do diodes permit current to flow in only one direction?
· Does the dictionary define electronics as the study of conduction of electricity?
Questions (with no auxiliary verb)
|Am/is/are||I/we/you/they /he/she/it||(a) physicist(s)/direct current?|
|Have/has||I/we/you/they/ he/she/it||a heater?|
· Can these devices be amplifiers?
· Are they physicists?
· Has this gadget a heater? or Does this gadget have a heater?
1. I am a physicist, aren’t I?
2. In the following examples, do is also the main verb (do you do /doesn't do etc.): *What do you do? I work in a shop.
*He's always so lazy. He doesn't do anything to help.
The verb to be
|I аm (I'm)||I||am not||(I'm not)|
|he||is||(he's)||he||is||not||(he's not or he isn't)|
|she||(she's)||she||(she's not or she isn't)|
|it||(it's)||it||(it's not or it isn't)|
|we||are||(we're)||we||are not||(we're not or we aren't)|
|you||(you're)||you||(you're not or you aren't)|
|they||(they're)||they||(they're not or they aren't)|
· I am/am not a physicist.
· He is/is not a famous scientist.
· Rectifier isn’t an electrical device.
· It isn’t easy to explain the operation of semiconductor devices.
Fill in the table.
|compare (to, with)|
|conduction conductivity conductor semiconductor||[kqn′dAkSn] (n) [kqn′dAkt] (v)|
|current AC (a.c.= alternating current) DC (d.c. = direct current)|
|phenomenon (pl.- phenomena)||явление|
2. Read and translate the following international words:
Nouns (n): academy, anode, author, battery, cathode, detector, diode, electricity, electrode, electron, electronics, element, energy, engineer, experiment, expert, gas, hobby, institute, method, million, operation, patent, pharmacology, principle, process, profession, radio, rouble, signal, student, symbol, vacuum, voltage.
Adjectives (adj): effective, electric, medical, negative, official, positive.
Verbs (v): register, process.
3. Consult the table above and write full sentences. Use is/are. Where possible change sentences to use isn’t/aren’t.
1. Rectifier …. an electrical device.
2. There … an anode and a cathode in a diode.
3. … it easy to explain the operation of semiconductor devices?
4. New devices … more powerful.
5. In some diodes there … a gas and current flows from one element to the other through a gas.
6. Look at Fig. X. This … a cathode and these … a plate and a battery.
7. The physical principles of this phenomenon may … quite different.
8. Anodes … positively charged electrodes by which the electrons leave a device.
9. Electronics … a science which studies the conduction of electricity in a vacuum, gases and semiconductors.
10. Cathodes (in electron tubes) … electrodes from which emission takes place.
11. Diode … a device that permits current to flow through it in only one direction.
12. There … a lot of analogue and digital equipment at our university.
4. Complete the sentences using the following verbs: emit(s), occur(s), flow(s), define(s),repel(s), attract(s), have(has).
1. We can … electronics as the study of conduction of electricity in a vacuum, in gases and in semiconductors.
2. The conduction of electricity in a vacuum for example … in vacuum tubes.
3. Though in some vacuum tubes current … from one element to the other through a gas.
4. Every vacuum tube diode … a cathode with a heater and a plate.
5. When the circuit is completed the cathode … electrons.
6. Negative voltage on the cathode … electrons.
7. Positive voltage on the plate … electrons.
5. Put the verb in brackets into the correct form. Insert always/never/
1. The current (flow) through the tube.
2. If a negative voltage is applied to the plate current (not flow).
3. Thus a diode (permit) current (flow) in only one direction.
4. A semiconductor diode also (conduct) current in one direction, but the physical principles, which (permit) it to do this (be) different.
5. We (use) diodes as rectifiers of alternating voltages, as detectors of radio signals, as switching devices, etc.
6. An English dictionary of electronics (define) this science as "the study of conduction of electricity in a vacuum, in gases and in semiconductors".
7. Do you (know) that in some diodes there is a gas, and current (flow) from one element to the other through a gas?
8. And can you (give) an example of conduction of electricity in a vacuum? This (occur) in vacuum tubes.
6. Mind the word-order and compile sentences from the following words:
A\tube\is\this\vacuum. – This is a vacuum tube.
7. Put questions to the following sentences:
1. This occurs in vacuum tubes. – Where…
2. A dictionary of electronics defines this science as "the study of conduction of electricity in a vacuum, in gases and in semiconductors". – How …
3. In vacuum diodes, for example, current flows through a vacuum in only one direction. – In what direction …
4. Current flows from one element to the other through a gas. – Through what …
5. If a negative voltage is applied to the plate, current does not flow. – When …
6. Positive voltage on the plate attracts the electrons. – What …
7. When heated the cathode emits electrons. – When …
8. Diodes are used as rectifiers of alternating voltages, as detectors of radio signals and as switching devices. – Are …
8. Form nouns from the following verbs using the suffix –tion and translate them:
amplify – усиливать (ток); amplification – усиление (тока)
attract – притягивать;
define – определять;
describe – описывать;
direct – направлять;
rectify – выпрямлять (ток).
9. Guess the meaning of the following adjectives paying attention to the suffix – ic:
atomic, automatic, classic, cubic, economic, dynamic, elastic, harmonic, geometric, kinetic, magnetic, periodic.
Read and translate word-combinations
A. start from the first component
|1. electronic anode conduction ionic||5. vacuum semiconductor diode crystal|
|2. electric detector magnetic circuit(цепь) anode cathode||6. molecular magnetic flow turbulent electron|
|3. high ultra-high perfect vacuum (совершенный) working||7. electric alternating current direct|
|4. electronic equivalent circuit(схема) typical five-electrode||8. positive negative plate (пластина) rotor|
В. start from the second component
|1. electron energy flow radiation||2. magnetization conduction currentelectrode||3. voltmeter сontrol сircuit(схема) (управление)|
Match the following sentences with their translations.
|1. The more words you know the better you will translate from English into Russian. 2. This occurs in vacuum tubes. 3. A dictionary of electronics defines this science as "the study of conduction of electricity in a vacuum, in gases and in semiconductors". 4. In vacuum diodes, for example, current flows through a vacuum in only one direction. 5. Diodes are used as rectifiers of alternating voltages, as detectors of radio signals and as switching devices. 6. In some diodes there is a gas, and current flows from one element to the other through a gas. 7. Current flows through the tube. 8. If a negative voltage is applied to the plate, current does not flow. 9. Thus, a diode permits current to flow in only one direction. 10. Positive voltage on the plate attracts the electrons. 11. When heated the cathode emits electrons. 12. Negative voltage on the cathode repels the electrons toward the plate.||a. Это происходит в вакуумных лампах. b. Диоды используются как вы-прямители переменных напря-жений как детекторы радио-сигналов и как переключатели. c. Чем больше слов вы будете знать, тем лучше будете переводить с английского языка на русский. d. Cловарь по электронике определяет эту науку как «исследование электропроводимости в вакууме, в газах и в полупроводниках». e. В вакуумных диодах, например, ток течет через вакуум только в одном направлении. f. В некоторых диодах есть газ, и ток проходит от одного элемента к другому через газ. g. При нагревании катод испускает электроны. h. Отрицательное напряжение на катоде отталкивает электроны по направлению к аноду. i. Положительное напряжение на аноде притягивает электроны. j. Ток течет через лампу. k. Если отрицательное напряжение приложено к аноду, ток не течет. l. Таким образом, диод позволяет току течь только в одном направлении.|
Choose as many words from the table оf ex. 1 as you can and form sensible sentences in Present Simple (affirmative, negative and interrogative).
For example: The operation of a vacuum diode is described in the text.
13. Mark the following sentences as true (T) or false (F). Then read the text “Diodes” and check yourself.
1. Electronics is the study of conduction of electricity.
2. In some vacuum tubes current flows through a gas.
3. A diode has a cathode with a heater and a plate.
4. The cathode emits electrons.
5. Negative voltage on the plate repels electrons.
6. If a positive voltage is applied current does not flow.
7. A diode permits current to flow in only one direction.
8. Diodes are used as rectifiers of alternating voltages, as detectors of radio signals, as switching devices, etc.
We can define electronics as the study of conduction of electricity in a vacuum, in gases and in semiconductors. The conduction of electricity in a vacuum, for example, occurs in vacuum tubes. Though in some vacuum tubes current flows from one element to the other through a gas.
Every vacuum tube diode has a cathode with a heater and a plate. When the circuit is completed the cathode emits electrons. Negative voltage on the cathode repels the electrons. Positive voltage on the plate attracts the electrons. The current flows through the tube. If a negative voltage is applied to the plate current does not flow. Thus a diode permits current to flow in only one direction.
A semiconductor diode also conducts current in one direction, but the physical principles, which permit it to do this are different. Diodes are used as rectifiers of alternating voltages, as detectors of radio signals, as switching devices.
Read the text again and complete the sentences with the correct ending.
1. Electronics is …
2. The conduction of electricity in a vacuum …
3. In some vacuum tubes current …
4. Every vacuum tube diode …
5. When the circuit is completed …
6. Negative voltage on the cathode …
7. Positive voltage on the plate …
8. If a negative voltage is applied to the plate…
9. A diode permits current to …
10. Diodes are used as …
Work in pairs. Ask your partner questions based on the text. Make sure you use correct auxiliary verb.
For example: Define electronics (How) - How can we define electronics?
1. The conduction in a vacuum occurs (Where) – …
2. Every vacuum diode has (What) – …
3. The cathode emits (What) – …
4. Negative voltage (Where) – …
5. … attract the electrons (What?) – …
6. The current flows through the tube (When?) – …
7. Current does not flow (Under what conditions?) – …
8. … to flow in only one direction (What?) – …
9. Diodes are used as (Where?) – …
Match the terms in Table A with their definitions in Table B
|Table A||Table B|
|1. rectifier 2. electronics 3. voltage 4. detector||a. The branch of physics and technology concerned with the design of circuits using transistors and microchips, and with the behavior and movement of electrons in a semiconductor, conductor, vacuum, or gas. b. An electromotive force or potential difference expressed in volts. c. An electrical device that converts an alternating current into a direct one by allowing a current to flow through it in one direction only. d. A device or instrument designed to detect the presence of a particular object or substance and to emit a signal in response.|
16. In groups draw a circuit of a diode and describe it. Start your description like this: This is a cathode. Its function is …. And this is a plate …
17. Summarize the text “Diodes” in 150 words paying special attention to the highlighted verbs in Present Simple.
Act as an interpreter. Translate the description of the operation of a semiconductor diode given by your group-mates from Russian into English.
19. Translate the text “Types of Diodes” with a dictionary in writing paying attention to the use of Present Simple.
There are several types of junction diodes, which either emphasize different physical aspects of a diode often by geometric scaling, doping level, choosing the right electrodes, or just an application of a diode in a special circuit, or are really different devices like the Gunn and laser diode and MOSFET.
Normal (p-n) diodes are usually made of doped silicon or, more rarely, germanium. Before the development of modern silicon power rectifier diodes, cuprous oxide and later selenium were used. Their low efficiency gives a much higher forward voltage drop (typically 1.4–1.7 V per “cell”) and requires a large heat sink (often an extension of the diode’s metal substrate) much larger than a silicon diode of the same current ratings would require. The vast majority of all diodes are p-n diodes found in some integrated circuits, which include two diodes per pin and a lot of internal diodes.
Avalanche diodes are the ones that conduct in the reverse direction when the reverse bias voltage exceeds the breakdown voltage. These are electrically very similar to Zener diodes, and are often mistakenly called Zener diodes, but the break down has a different mechanism, the avalanche effect. This occurs when the reverse electric field across the p-n junction causes a wave of ionization, reminiscent of an avalanche, leading to a large current. The difference between the avalanche diode (which has a reverse breakdown of above about 6.2 V) and the Zener diode is that the channel length of the former exceeds the “free path” of the electrons, so there are collisions between them on the way out. The only practical difference is that the two types have temperature coefficients of opposite polarities.
There also exist crystal diodes, constant current diodes, Esaki or tunnel diodes, gun-diodes, light-emitting diodes (LEDs), laser diodes, photodiodes, etc.
Indicators such as some "magic eye" tubes and the type 6977 fluorescent-anode type have glowing electrodes.
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.
22. Find more information about conduction of current in a semiconductor diode and tell your group mates.
am/is/are + -ing
|he/she/it||is||(= he's etc.)||decreasing|
|we/you/they||are||(= we're etc.)||insulating|
· I am plugging this device in today.
· Look! Current is flowing through the tube.
· They are placing the grid between the cathode and the plate at the moment.
Verbs that end in –e (make) – ing: make-making
Verbs that end in –ie (lie) – ing: lie-lying
|I he/she/it we/you/they||am not is not are not||controlling decreasing insulating|
· I am not working as a physicist now.
· These devices are not heating this week.
· Look! They are not placing the grid between the cathode and the plate.
|Am Is Are||I he/she/it we/you/they||controlling? decreasing? insulating?|
· Why aren’t these devices heating this week?
· Look! They are placing the grid between the cathode and the plate at the moment, aren’t they?
Adjectives and adverbs
1) Adjective + noun
· a modern amplifier
· a good conductor
· a precise definition
But: Look/feel/smell/taste/sound/get + adjective
2) Verb + adverb
Adjective + -ly = adverb
|Adjective Adverb||quick quickly||bad badly||sudden suddenly||careful carefully||heavy heavily||good well|
· to control well
· to conduct readily
· to operate quickly
Degrees of Comparison
|cheap – cheaper –the cheapest nice – nicer –the nicest big – bigger –the biggest early – earlier –the earliest||expensive – more expensive – the most expensive interesting – more interesting – the most interesting|
But: good – better – the best
bad – worse – the worst
little – less – the least
much/many – more – the most
1. Fill in the table.
|control (п,v)||control||управление, управлять||[kqn′trqul]|
|decrease||decrease||[′di:kr i:s] (n) [di:′kri:s] (v)|
|depend (on, upon)|
|increase||increase||increasingly||[′inkris] (п) [in′kri:s] (v)|
|insulator insulation||диэлектрик/ непроводник изоляция|
2. Read and translate the following international words:
Nouns (n): effect, function, idea, ion, material, metal, milliampere, reflector, result, secret, spiral, triode, volt
Verbs (v): compensate, control
Adjectives (adj): modern, miniature, standard
3. Write the following verbs with –ing. Mind the spelling.
Control,decrease,depend,increase,place,result,conduct, insulate, heat, emit, flow, have, apply, use.
4. Look at Fig.1 and complete the sentences with the following verbs in the correct form: attract, repel, heat, flow, emit.
Fig.1. Electron flow in a vacuum tube
1. The heater … the cathode.
2. The cathode … electrons.
3. Negative voltage on the cathode … the electrons.
4. Positive voltage on the plate … the electrons.
5. Current … from one element to the other through a gas.
5. Make up questions from these words. Use is or are and put the words in order.
5. the\between\grid\being placed\the\cathode\and\the\plate.
8. a\small\negative\voltage\being applied\to\the\grid.
10. being used\for\amplification\a\triode.
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