Ответы на тесты по предмету Английский язык (18796 вопросов)

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. paragraph
2. quatation-marks
3. identation
4. printing

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. composed matter
2. reporter
3. publisher
4. foreword

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. handwritten newspaper
2. social customs
3. pamphlet
4. title

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. printed publication
2. issue
3. economic conditions
4. journalism

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. free press
2. stamp
3. powerful force
4. rule

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. to be concentrated on
2. political news
3. successful newspaper
4. to attract

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. argument
2. to disarm
3. to befriend
4. getaway

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. opportunity
2. to be illiterate
3. to highlight
4. society

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. to emphasize
2. to publish article
3. yellow sheet
4. human interest

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. news reporter
2. to cover
3. commentary
4. to search out

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. pictorial magazine
2. periodical
3. newsweekly
4. entertainment material

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. to solve a mystery
2. interference
3. exclusive rights
4. to mount a campaign

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. in the interests of somebody
2. to be instilled into the heart of someone
3. to work hand-in-hand with
4. to look at something through rosy glasses

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. personal ads
2. to place an advert
3. to scan the newspaper
4. mainstream newspapers

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. teaching instrument
2. creative ideas
3. current events
4. area of interests

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. the vast majority (of)
2. to put pressure (on)
3. to appeal decision
4. to set rules

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. to earn a living
2. to make headlines
3. to enter the mainstream
4. to exhibit enthusiasm

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. to hand out leaflets
2. to test patience
3. to recognize a need for
4. to have serious consequences

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. transitory events
2. to disseminate stories
3. reportage
4. to feel helpless

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. newsroom
2. lone reporter
3. well-documented story
4. damaging information

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. government records
2. civil organizations
3. vigilant public
4. government bodies

Выберите соответствия между английскими словами и выражениями и их русскими эквивалентами
1. collection of news
2. transmission of news
3. to tell the difference
4. to support theory

Прочитайте текст и определите, какой из заголовков соответствует тексту
Of the many types of tubes which are in use, the simplest is the diode.
This is a two-element tube which consists of an emitter of electrons (the cathode) and a collector of electrons (the plate or the anode).
The term diode refers to the number of electrodes within the tube. The main function of the two-element tube is as converter of power. By this we understand that by means of the diode the electric power can be converted. Alternating voltage is converted in the form of pulsating direct current (the convertion of a. c. power into d. с power). This is the process of rectification.

Прочитайте текст и определите, какой из заголовков соответствует тексту
The triode, or three electrode tube, is an elaboration of the diode.
The diode consists of two electrodes. They also appear in the triode and they constitute the basis of the triode. In the triode the third electrode (the control grid) is added in the space between the emmitter and the plate.
The control grid is a metal structure which may be of different shape, depending upon the design of the tube.
The basic function of the triode is to amplify the current, or voltage or electric power. In this process of amplification the control grid plays a most important role.

Прочитайте текст и определите, какой из заголовков соответствует тексту
A metal rectifier, a widely used form of rectifier, is the metallic type consisting essentially of a number of units formed by depositing a layer of semiconducting material, such as copperoxide on a metal conducting base. These units, generally in the form of washers, are assembled on rods under pressure, the number of units employed being determined by the voltage. Each unit has the peculiar property of passing current freely when the semi-conducting layer is positive and allowing practically no current to flow in the opposite direction. This form of rectifier has the great advantage of strength, absence of moving parts and relative simplicity.

Прочитайте текст и определите, какой из заголовков соответствует тексту
Another type of rectifier is represented by various kinds of two-electrode valves, or diodes. These consist of a glass tube or bulb containing an electron-emmiting member (the cathode) and an electrode (called the anode) which collects the emitted electrons and causes a flow of current so long as it is positive with respect to the cathode. The cathode heater is supplied with a suitable voltage from the transformer secondary to provide the heating necessary for the emission of electrons.

Прочитайте текст и определите, какой из заголовков соответствует тексту
Ultra-violet rays are familiar to most people as the particular art of sunlight that is "health-giving".
The effect of the ultra-violet rays is to produce in the skin the vitamin that is important for the promotion of bone-growth.
The use of these rays in diagnosis is a powerful weapon of medicine.
One of the most valuable uses of ultra-violet rays in industry is the testing of the quality of certain goods.

Прочитайте текст и определите, какой из заголовков соответствует тексту
It was found that if a sealing-wax rod is rubbed with a woolen cloth, and a rod of glass is rubbed with a silken cloth, an electric spark will pass between the sealing-wax rod and the glass rod when they are brought near one another. Moreover, it was found that a force of attraction operates between them. An electrified sealing-wax is repelled, however, by a wax rod, and also an electrified glass rod is repelled, by a similar glass rod.

Прочитайте текст и определите, какой из заголовков соответствует тексту
The polarity of a charge may be determined by means of an electroscope. We charge the electroscope negatively by touching the ball with a rod of hard rubber which is rubbed with flannel or silk. If the unknown charge is brought to the electroscope it will induce on the ball a charge of opposite polarity and on the gold leaves a charge of the same polarity as that of the unknown charge. Therefore, if the unknown charge is negative, the gold leaves will repel each other; if it is positive, they will attract.

Прочитайте текст и определите, какой из заголовков соответствует тексту
Conductors are materials that have a large number of loosely bound valence-ring electrons; these electrons are easily knocked out of their orbit and are then referred to as free electrons. Insulators are materials in which the valence-ring electrons are tightly bound to the nucleus. In between the limits of these two major categories is a third general class of materials called semiconductors.

Прочитайте текст и определите, какой из заголовков соответствует тексту
The simplest combination of elements constituting an electron tube is the diode. It consists of a cathode, which serves for emitting the electrons, and a plate or anode surrounding the cathode, which acts as a collector of electrons. Both electrodes are enclosed in a highly evacuated envelope of glass or metal. If the cathode is indirectly heated, there must be a heating spiral or a heater. The size of diode tubes varies from tiny metal tubes to large-sized rectifiers. The plate is generally a hollow metallic cylinder made of nickel, molybdenum graphite, tantalum or iron.

Прочитайте текст и определите, какой из заголовков соответствует тексту
A basic law of electricity states that like charges repel each other and unlike charges attract each other. Electrons emitted from the cathode of an electron tube are negative electric charges. These charges may be either attracted to or repelled from the plate of a diode tube, depending on whether the plate is positively or negatively charged.

Прочитайте текст и определите, какой из заголовков соответствует тексту
By applying a potential difference (voltage) from a battery or other source between the plate and cathode of a diode, an electric field is established within the tube. The lines of force of this field always extend from the negatively charged element to the positively charged element. Electrons, being negative electric charges, follow the direction of the lines of force in an electric field.

Прочитайте текст и определите, какой из заголовков соответствует тексту
The term space charge is applied to the cloud of electrons that is formed in the interelectrode space between cathode and plate. Since it is made up of electrons, this cloud constitutes a negative charge in the interelectrode space that has a repelling effect on the electrons being emitted from the cathode. The effect of this negative space charge alone, therefore, is to force a considerable portion of the emitted electrons back into the cathode and prevent others from reaching the plate.

Прочитайте текст и определите, какой из заголовков соответствует тексту
The control grid was added between the cathode and plate of a diode and so it provided the resulting triode tube with the ability to amplify tiny signals. The control grid in this tube is a circular spiral of a number of turns of fine wire that completely surround the cathode. Because of its open construction the grid does not directly hinder the flow of electrons to the plate, but when a voltage is placed on the grid it has a profound effect on the electric field between cathode and plate and, hence, on the total electron flow.

Прочитайте текст и определите, какой из заголовков соответствует тексту
A diode is a two-element electron tube that consists of a cathode and an anode or plate acting as an electron collector. By applying a positive voltage to the plate of a diode, an electric field is established between cathode and plate that attracts electrons emitted from the cathode to the plate.

Прочитайте текст и определите, какой из заголовков соответствует тексту
Plate current is the flow of electrons from cathode to the plate and their return to the cathode through the external circuit. Plate current flows in a diode when the plate is made positive with respect to the cathode. No current flows when the plate is negative with respect to the cathode. This is called unidirectional conduction.

Прочитайте текст и определите, какой из заголовков соответствует тексту
The cloud of electrons formed in the space between cathode and the plate is called space charge. The space charge is negative and hence has a repelling effect on electrons emitted from the cathode. The amount of the plate current depends on the space charge and the relative strength of the electric field set up by the positive plate voltage.

Прочитайте текст и определите, какой из заголовков соответствует тексту
The electron beam may be deflected either electrostatically or magnetically. Let us consider electrostatic deflection. An electrostatic field can be produced between two metal plates simply by applying a potential difference between them. Electrons entering the field between the deflecting plates will be bent in the direction of the lines of force, that is, they will be attracted toward the positive plate. The resultant path of the beam will be the net effect between its forward velocity and its deflection. As a result the electron spot is deflected upward or downward depending upon the polarity of the voltage on the plate.

Прочитайте текст и определите, какой из заголовков соответствует тексту
Now let us turn to cathode-ray tubes (abbreviated CRT) that provide a visual representation of voltage and current waveforms. Cathode-ray tubes consist of three basic components: 1. the electron gun, 2. a deflection system, 3. a fluorescent screen. These essential parts of a cathode-ray tube are mounted inside a highly evacuated, funnel-shaped glass envelope the large end of which has the fluorescent screen coated upon the inside surface.

Прочитайте текст и определите, какой из заголовков соответствует тексту
Among the most common meters used there are the ohmmeter, the ammeter and the voltmeter. The ohmmeter is used to measure the value of resistance. It consists of a milliammeter calibrated to read in ohms, a battery and resistors. The meter is connected in parallel and the circuit is not opened when its resistance is measured. The readings on the scale show the measured value.
The ammeter is used to measure the value of current. When the ammeter is used the circuit should be opened at one point and the terminals of the meter should be connected to it. One should take into consideration that the positive terminal of the meter is connected to the positive terminal of the source; the negative terminal - to the negative terminal of the source.
The ammeter should be connected in series. The readings on the scale show the measured value.

Прочитайте текст и определите, какой из заголовков соответствует тексту
A resistor is one of the most common elements of any circuit. Resistors are used:
1. to reduce the value of current in the circuit;
2. to produce IR voltage drop and in this way to change the value of the voltage.
When current is passing through a resistor its temperature rises high. The higher the value of current the higher is the temperature of a resistor. Each resistor has a maximum temperature to which it may be heated without a trouble. If the temperature rises higher the resistor gets open and opens the circuit.
Resistors are rated in watts. The watt is the rate at which electric energy is supplied when a current of one ampere is passing at a potential difference of one volt.

Прочитайте текст и определите, какой из заголовков соответствует тексту
A capacitor is one of the main elements of a circuit. It is used to store electric energy. A capacitor stores electric energy provided that a voltage source is applied to it. The main parts of a capacitor are metal plates and insulators. The function of insulators is to isolate the metal plates and in this way to prevent a short.
There are two common types of capacitors in use nowadays: a fixed capacitor and a variable one. The plates of a fixed capacitor cannot be moved; for this reason its capacity does not change. The plates of a variable capacitor move; its capacity changes. The greater the distance between the plates, the less is the capacity of a capacitor. Variable capacitors are commonly used by radiomen; their function is to vary the frequency in the circuit. Fixed capacitors are used in telephone and radio work.

Прочитайте текст и определите, какой из заголовков соответствует тексту
Conductors are materials having a low resistance so that current easily passes through them. The lower the resistance of the material, the more current can pass through it.
The most common conductors are metals. Silver and copper are the best of them. The advantage of copper is that it is much cheaper than silver. Thus copper is widely used to produce wire conductors. One of the common functions of wire conductors is to connect a voltage source to a load resistance. Since copper wire conductors have a very low resistance a minimum voltage drop is produced in them. Thus, all of the applied voltage can produce current in the load resistance.

Прочитайте текст и определите, какой из заголовков соответствует тексту
Materials having a very high resistance are called insulators. Current passes through insulators with great difficulty.
The most common insulators are air, paper, rubber, plastics.
Any insulator can conduct current when a high enough voltage is applied to it. Currents of great value must be applied to insulators in order to make them conduct. The higher the resistance of an insulator, the greater the applied voltage must be.
When an insulator is connected to a voltage source, it stores electric charge and a potential is produced on the insulator. Thus, insulators have the two main functions:
1. to isolate conducting wires and thus to prevent a short between them and
2. to store electric charge when a voltage source is applied.

Прочитайте текст и определите, какой из заголовков соответствует тексту
A transformer is used to transfer energy. Due to the transformer electric power may be transferred at a high voltage and reduced at the point where it must be used to any value. Besides, a transformer is used to change the voltage and current value in a circuit.
A two-winding transformer consists of a closed core and two coils (windings). The primary winding is connected to the voltage source. It receives energy. The secondary winding is connected to the load resistance and supplies energy to the load.

Прочитайте текст и определите, какой из заголовков соответствует тексту
Current transformers are used for operating ammeters, wattmeters, and other measuring devices. They produce in the meters a current lower than the measured current but proportional to it.
Current transformers also insulate the instrument from the circuit which is being measured. This is necessary for high voltage circuits.

Прочитайте текст и определите, какой из заголовков соответствует тексту
Current is a flow of electricity through a circuit. Let us consider two main types of current: direct and alternating. A direct current (d.c.) flows through a conducting circuit in one direction only. It flows provided a direct voltage source is applied to the circuit.
An alternating current (a.c.) is a current that changes its direction of flow through a circuit. It flows provided an alternating voltage source is applied to the circuit. Alternating current flows in cycles. The number of cycles per second is called the frequency of the current. In a 60-cycle alternating current circuit the current flows in one direction 60 times and in the other direction 60 times per second.

Прочитайте текст и определите, какой из заголовков соответствует тексту
Alternating current (a.c.) is converted into direct current by means of a rectifier.
A half-wave rectifier consists of a diode in series with a resistance. In order to put a rectifier into operation, a source of a.c. should be applied to it. When an a.c. source is applied the diode begins to conduct. The rectifier passes currents during positive half-cycles of the applied voltage. That is why it is called a half-wave rectifier. When the device operates direct current (d.c.) flows in the same direction. It is a pulsating current. Since pulsations should be eliminated, a filter is applied. Pulsations are eliminated by means of this filter.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Electronics is a rather young 1____________. It belongs to the twentieth century. Within a short period it has become a powerful means of progress.
Electronics surrounds us everywhere. Television, radio-receiving, tape-recording - are all based on 2_____________. The ideas of electronics are embodied in 3______________ technology and means of automation, biology and genetics which have 4______________ biotechnology as a new branch of the national economy.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Electronic computers are widely used in 1____________ research, in planning and controlling our national economy. Very complicated electronic 2____________ control the work of huge plants and power stations; even whole industries are 3______________ by electronic robots. Planes and rockets are also electronically controlled.
Electronics has sharpened our vision and given us chance to see the microworld more clearly. It helps 4___________ discover new and puzzling phenomena of nature.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Due to electronics the first man-made 1_____________ was launched into space, and now man has already set his foot on the Moon, sends probes to distant planets. Radioelectronic 2______________ ensure reliable communication with space probes at distances of millions of kilometers, relay 3_______________ of distant planets. The greatest 4______________ of electronics is in the field of communications.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
The range of radio 1______________ in space is extending more and more. There is every reason to believe that radio links may be set over 2________________ of 100 million kilometers or even more.
Now we cannot imagine our life without electronics.
But it all began with the 3_______________ of radio. It was our Russian scientist A.S. Popov who discovered the principles of wireless communication that finally led to the development of 4________________ tubes for use in various communication devices.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
1______________ is the technology of constructing electronic circuits and devices in extremely small packages by various techniques. This 2_______________ is also referred to as microminiaturization.
The increasing complexity of electronic systems over the past 30 years has made the evolution of microelectronics inevitable. During this 3_______________, the electron tubes in the early electronic systems have been replaced by solid-state discrete devices and integrated circuitry; and these, in turn, 4_____________ way to medium- and large-scale integrated circuitry.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Microelectronics today encompasses thin-film, 1________________, hybrid, and integrated circuit technology. These approaches (and combinations of them) are being applied in 2____________ branch of electronics.
Integrated circuits that combine all the 3__________________ of a complete electronic circuit on a single chip of silicon can be produced. The implications of this in the microelectronic evolution are easily 4_______________. Let us compare a conventional J/K flip-flop circuit incorporating solid-state discrete devices and the same type of circuit employing integrated circuitry.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
The conventional circuit would require approximately 40 separate discrete 1___________, 200 connections, 40 hermetic seals, and 300 separate processing operations with each operation, seal, and connection representing a possible source of failure. However, if all the elements of this circuit are integrated upon one chip of silicon, the 2_____________ of connection drops to about 14. All circuit elements are interconnected inside the package by a process 3_______________ as vapour metallization; instead of 40 hermetic seals there is one, and the three 4_______________ processing operations are reduced to approximately 30.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Electronics is one of the main 1_____________, which forms the 2_______________ basis for using these new methods. Electronics studies the problems connected with the application of instruments and 3_____________, the action of which is based on the utilization of various phenomena that result from the movement of 4______________ through vacuum, gases and solid bodies.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Electronics surrounds us everywhere. Television, tape-recording, radio-receiving - electronics is at the heart of them all. But that is only a small part of 1_______________ and not the most important at that. Extremely complicated electronic systems 2______________ the work of huge plants, enterprises and 3_______________ stations. Electronic appliances are indispensable for planning and controlling our national 4_______________.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Electronic computers are widely used in 1_______________ research аnd industrial designing. Huge radio-telescopes, 2_____________ with sensitive instruments and 3_______________ amplifiers enable man to gain an insight into the remotest corners of space, 4_________________ new and puzzling phenomena of nature.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Electronic computers 1______________ the trajectories of spaceships, help prepare, launch and monitor the rockets that carry the most complicated and sophisticated equipment. Radio-electronic 2_____________ ensure reliable communication with space probes at distances amounting to scores of 3______________ of kilometres, relay telephotos of distant planets. Hundreds of 4______________ devices perform various tasks on board every satellite and spaceship. It may be said that in the near future electronics will surely make great strides and help the humanity gain new victories in science and engineering.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
The realm of 1 ______________ of to-day influences almost, every aspect of human activity, while it was only in the beginning of our century that the basic idea, which was to develop into one of the most astonishing sciences of our time, was conceived. It was our Russian 2______________ A. S. Popov, who discovered the principle of wireless 3______________ that finally led to the development of electronic 4______________ for use in various communication devices.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Intensive 1______________ of radio-location began in the early forties. All these years the vacuum 2_______________ was the heart of electronics and, hence, the field of 3______________ was usually defined as the study of the motion of electrons in vacuum tubes. However, it was found that small, controlled 4______________ of gas introduced into a "vacuum tube" could make it perform switching, rectifying and other jobs. To include the category of gas-filled tubes, "vacuum tubes" became converted to "electron tubes" and the science of electronics was expanded to include the study of electron motion in gases.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
The first semiconductor 1______________ was invented in 1948. It meant another important advance in the development of 2_____________. Semiconductors possess a number of valuable 3______________ over electron vacuum tubes, - miniature dimensions and high 4______________. Thus electronics became the study of electron motion in solids. The realm of electronics widened still more. This opened up other fields of application for electronics.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
A laser is a quantum electronic 1______________. It is a machine for making and concentrating light 2______________ into a very intense beam. The letters LASER stand for Light Amplification by Stimulated Emission of Radiation. The light 3______________ by a laser is much more intense than ordinary light. With ordinary light, all the light waves are of 4_____________ lengths. With lasers, all the light waves are of the same length, and this increases the intensity.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
1____________ is an extremely simple-looking 2_______________. It is nothing more than a cylinder of synthetic ruby about 1/4 inches in 3_____________ and 1 1/2 inches long mounted in the centre of a spiral coil of glass. The coil is a xenon-filled flash 4_______________, very much like the ones used by photographers for taking flash pictures.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
The laser beam is 1_____________ by exciting the atoms of a suitable material - ruby is one - until most of the atoms have electrons orbiting in a higher energy level than usual. The excitation is then stopped and all the excited electrons fall back together, to their normal orbits, each one emitting a pulse of 2______________ of the same energy. In this way an intense beam of light is generated for a very short time. And 3______________ pulse or wave-train in this beam is in step with every other pulse. In this way a beam of light is obtained which is both monochromatic and coherent and easy to focus. This light is reflected by the mirror at one end of the tube. It can only escape at the other 4______________ of the tube.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
The range of the 1______________ use is expanding with 2______________ passing year. The use of picoseconds laser pulses will help to 3______________ faster and more powerful microchips information circuits and computers by mapping more exactly the routes electrons take through semiconductor materials, the rates they travel and the effects of impurities. 4______________ lasers will help research on interactions among molecules in liquids.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Lasers are widely used in 1_______________. In Moscow an All-Union Centre for Using Lasers in Surgery has been set up. The first step was made in 1970 by 2_____________ A. Vishnevsky who used a small-capacity 3______________ installation experimenting on animals. Russian scientists have produced Scalpel-1 installation which is widely used in our 4_____________ and is exported to many other countries.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Lasers are used in 1________________ and in agriculture. Russian scientists have developed a 2______________ instrument - the laser projection 3_______________ (the work received the USSR State Prize). The tremendous brightness of laser radiation 4________________ it possible to project clear images of microobjects onto large screens, magnified 15,000 times.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Laser beams 1_____________ it possible not only to transmit light 2______________ over great distances, but also to encase it in very thin glass filaments - waveguides. It is possible to transmit simultaneously thousand telephone 3______________ and many 4______________ programmes over a single guide a tenth of a millimetre thick.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Thermionic emission is the most important and one most commonly used in electron 1_______________. In this 2________________ the metal is heated, resulting in increased thermal or kinetic 3________________ of the unbound electrons. Thus, a greater number of electrons will attain sufficient speed and energy to escape from the surface of the emitter. The number of electrons released per unit area of an emitting surface is related to the absolute 4_________________ of the cathode and a quantity of the work an electron must perform when escaping from the emitting surface.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
When 1__________________ electrons suddenly strike a metallic 2_______________ they give up their kinetic 3_________________ to the electrons and atoms which they strike. Some of the bombarding electrons collide directly with free 4_________________ on the metal surface and may knock them out from the surface. The electrons freed in this way are known as secondary emission electrons, since the primary electrons from some other source must be available to bombard the secondary electron-emitting surface.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
We are finally ready to apply the knowledge we gained in previous sections about electrons, vacuum 1_________________ and transistors to some practical matters. In the following sections we shall consider a variety of circuits employing electron tubes and transistors. Circuits are 2_________________ of tubes or transistors with other components, such as resistors, capacitors and inductors, and form the 3________________ building blocks of electronic systems: radio, automatic computer and so on. To understand the systems, you must be familiar with the circuits that 4_______________ them up.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Now we shall discuss amplifier 1________________, or more specifically, audio amplifiers. An amplifier is an electron tube or transistor circuit, which 2_________________ up an ac signal applied to its input. It is called a voltage amplifier if the magnitude of the output 3__________________ from the amplifier is considerably greater than that of the input voltage. As a matter of fact the ratio of the output voltage to the 4__________________ voltage is called the amplification or gain of the amplifier.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
There are 1_______________ power amplifiers. These are similar to voltage amplifiers, except that their main 2__________________ is to supply a considerable amount of 3________________ i. e. voltage times current to the output or load 4________________, although the ac input signal may not draw any grid current and, hence, the input power may be zero.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
When a number of 1_______________ are hooked up in series so that the output of one serves as the input to the next amplifier stage, the function of the early stages is usually to 2______________ up the voltage to a high 3_______________, while the last stage builds up the power to a level sufficient to operate an output device. Audio amplifiers amplify electrical ac signals that have a frequency range corresponding to the range of human hearing, or from about 20 to 15,000 cycles per 4________________.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
The reflection of 1_______________ waves from aircraft had been observed in England in the early 1930s and the possibility for aircraft detection was discussed in 1934. It was soon realized that radio waves would be the 2________________ alternative to the existing inadequate acoustic warning equipment, which merely 3________________ for the sound of aircraft engines and had too short a range for proper warning of approach of last aircraft. In contrast, experiments indicated that radar could give a warning when the 4_________________ was 100 miles or more away.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
The principles of radar in a simplified form might be stated as 1________________:
1. electromagnetic radiation at high radio frequencies is 2________________ to detect and locate remote reflecting objects;
2. the radiation is sent out in pulses of a few microseconds’ duration, separated by intervals many times the duration of each pulse;
3. the pulses are returned from the reflecting objects and the returns are detected and displayed by receiving equipment placed at the point of transmission;
4. the distance to the 3________________ is determined by measurement of the time it took the pulses to reach the targets from the transmission equipment and return to it;
5. the directions of the targets are determined by use of highly directive radio 4__________________.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
Sonar (Sound Navigation and Ranging) is employed to locate submerged enemy 1________________. Like radar it is an echo-ranging 2__________________. It operates in the following way - a ship 3________________ a sound wave into the water. Encounting an obstacle the wave is reflected back to the ship, which – since the speed of sound through water is known - determines its distance from the object from the time it took the echo to return. To create the original sound wave, the ship generates 4________________ signals in а transmitter; it then sends these to a transducer, positioned on its keel as deeply in the water as possible. The transducer converts the signals into sound and transmits them through the water.

Прочитайте текст и заполните пропуски подходящими по смыслу словами
The 1________________ is basically a three-section device composed of two outside sections and a middle section. The two outside 2______________ are doped so that they are either P- or N-tуре, and the middle section is doped opposite to the outside sections. Transistors are 3_________________ as NPN or PNP according to the doping of the sections or elements. When the two outside sections are N-type 4_________________ and the middle section is a P-type, the transistor is an NPN-type. When the two outside sections are P-types and the middle is N-type, the transistor is a PNP-type.

Прочитайте текст
Experts believe that some boys are spending so much time playing computer games and watching violent films that they are living in a fantasy world. When girls talk about using home computers, they often discuss different types of software that they use for learning. Boys simply talk about computer games. When 14-year-old girls were asked what they would like to do in the future, they mentioned realistic jobs such as vet, teacher or doctor. The boys' answers were either very vague such as, "I just want to be happy and have lots of money" or unrealistic and they said things such as, "I want to be a fighter pilot”.
Ответьте на вопрос
What is the topic of girls’ discussion about using home computers?

Прочитайте текст
A lot of knowledge is a dangerous thing for addicts of the Internet. Information is becoming the drug of the new century.
The research, conducted among 1000 managers in Britain, America, Europe and the Far East shows that, as information sources such as the Internet and cable news channels proliferate, we are witnessing the rise of a generation of dataholics.
Ответьте на вопрос
What are people who use the Internet a lot called?

Прочитайте текст
The quest for information can lead to stress. Almost two-thirds said their leisure time had been curtailed as a result of having to work late to cope with vast amounts of information; 70 percent reported loss of job satisfaction and tension with colleagues because of information overload.
Ответьте на вопрос
Why do you have to spend much leisure time to find the information you need?

Прочитайте текст
The study investigated the habits of the children of 300 managers and found 55 per cent of parents were concerned their children would become information junkies.
Forty-six per cent of parents believed their children spent more time on their PCs than interacting with friends. In one case a child had to be wheeled with his computer to the dinner table.
Ответьте на вопрос
Why were the parents so concerned?

Прочитайте текст
Health questions have been raised by the people who sit all day in front of the video display terminals (VDTs) of their computers. Are computer users getting bad radiation? What about eyestrain? And what about the age-old back problem, updated with new concerns about workers who hold their hands over a keyboard? What about repetitive-action injury also known as carpal tunnel syndrome? What about the risk of miscarriage?
Ответьте на вопрос
Who often asks questions about health?

Прочитайте текст
Meanwhile, there are a number of things workers can do to take care of themselves. A good place to begin with is an ergonomically designed workstation. Ergonomics is the study of human factors related to computers. A properly designed workstation takes a variety of factors into account, such as the distance from the eyes to the screen and the angle of the arms and wrists.
Ответьте на вопрос
Why is ergonomics important for designing workstations?

Прочитайте текст
You can't carry a computer as easily as you can a newspaper, but you'll find a lot of other things to like about online newspapers.
More than 100 daily papers in the United States and Canada publish electronic editions. You can connect with them using your computer, a modem and an Internet browser.
Online newspapers have the most up-to-date news. Both USA Today and The San Jose (California) Mercury News add stories to their electronic editions throughout the day.
Ответьте на вопрос
How can you connect with electronic editions of daily papers?

Прочитайте текст
Ever wish you had saved a newspaper article, after you threw it away? With electronic newspapers, you can go online and find old articles you need for class discussions, reports or your own personal use.
"Everything that's appeared in The Mercury News for the last 10 years is available on our Web site or America Online," said Barry Parr of The San Jose Mercury News. "There are more than a million news stories in our database."
Ответьте на вопрос
What is the advantage of electronic newspapers?

Прочитайте текст
The first "hackers" were students at the Massachusetts Institute of Technology (MIT) who belonged to the TMRC (Tech Model Railroad Club). Some of the members really built model trains. But many were more interested in the wires and circuits underneath the track platform. Spending hours at TMRC creating better circuitry was called "a mere hack." Those members who were interested in creating innovative, stylistic, and technically clever circuits called themselves (with pride) hackers.
Ответьте на вопрос
What were the students who called themselves hackers interested in?

Прочитайте текст
Much personal information about individuals is now stored in computer files. An unauthorized person with access to this information could use it for blackmail. Also, confidential information about a company's products or operations can be stolen and sold to unscrupulous competitors. (One attempt at the latter came to light when the competitor turned out to be scrupulous and turned in the people who were trying to sell him stolen information.)
Ответьте на вопрос
When can personal information be used for blackmail?

Прочитайте текст
The software for a computer system is often more expensive than the hardware. Yet this expensive software is all too easy to copy. Crooked computer experts have devised a variety of tricks for getting these expensive programs printed out, punched on cards, recorded on tape, or otherwise delivered into their hands. This crime has even been perpetrated from remote terminals that access the computer over the telephone.
Ответьте на вопрос
Why are there so many tricks for getting expensive software?

Прочитайте текст
Personal computers (PC) are small, relatively inexpensive computers for an individual user. Their price can be from a few hundred dollars to thousands of dollars. All are based on the microprocessor technology that enables manufacturers to put an entire CPU on one chip. Personal computers are used in business for word processing, accounting, desktop publishing. At home, the most popular use for personal computers is for playing games.
Ответьте на вопрос
What are personal computers used for?

Прочитайте текст
Personal computers first appeared in the late 1970s. One of the first and most popular personal computers was the Apple II, made in 1977 by Apple Computer. Then, in 1981, IBM (International Business Machines) made its first personal computer, known as the IBM PC. The IBM PC quickly became the most popular personal computer.
Ответьте на вопрос
What were the first models of PC?

Прочитайте текст
Computer programs are called software. Software is instructions for hardware (the machines) to do work. Software is often divided into two categories:
Systems software: the operating system and all the utilities that enable the computer to function.
Applications software: programs that do real work for users. For example, word processors, spreadsheet programmes, and games are applications software.
Ответьте на вопрос
What are applications software?

Прочитайте текст
Hardware are computer components that you can touch, like disks, disk drives, monitors, keyboards, printers, boards, and chips. But you cannot touch software. Software exists as ideas, concepts, and symbols. A computer without software is dead - you need software to make the computer work.
Ответьте на вопрос
What is hardware?

Прочитайте текст
Peripheral devices are computer devices, such as a CD-ROM drive or printer. Peripheral devices can be external, such as a mouse, keyboard, printer, monitor, and scanner. Peripheral devices can be internal, such as a CD-ROM drive or internal modem.
Ответьте на вопрос
Are peripheral devices only external?

Прочитайте текст
Computer keyboard is the set of typewriter-like keys that enables you to enter data into a computer. Computer keyboards are similar to electric-typewriter keyboards but contain additional keys. The keys on computer keyboards are often classified as follows:
alphanumeric keys - letters and numbers;
punctuation keys - comma, period, semicolon, and so on;
special keys - function keys, control keys, arrow keys, Caps Lock key, and so on.
Ответьте на вопрос
What are computer keyboards similar to?

Прочитайте текст
There is no standard computer keyboard, although many manufacturers imitate the keyboards of PCs. There are actually three different PC keyboards: the original PC keyboard, with 84 keys; the AT keyboard, also with 84 keys; and the enhanced keyboard, with 101 keys. The three differ somewhat in the placement of function keys, the Control key, the Return key, and the Shift keys.
In addition to these keys, IBM keyboards contain the following keys: Page Up, Page Down, Home, End, Insert, Pause, Num Lock, Scroll Lock, Break, Caps Lock, Print Screen.
Ответьте на вопрос
How many keys has enhanced keyboard?

Прочитайте текст
Hard disk drive is the mechanism that reads and writes data on a hard disk. Hard disk drive has many inflexible platters (discs) coated with magnetic material. Read/write heads can record computer data on these discs. A typical hard disk rotates at 3,600 revolutions per minute, and the read/write heads ride over the surface of the disk on a cushion of air 25 micron deep. Hard disk drives (HDDs) for PCs generally have seek times of about 12 milliseconds or less. Hard disk drives are sometimes called Winchester drives. Winchester is the name of one of the first popular hard disk drive technologies developed by IBM in 1973.
Ответьте на вопрос
How are hard disk drives sometimes called?

Прочитайте текст
Microprocessor is a silicon chip that contains a CPU. The terms microprocessor and CPU are used interchangeably. At the heart of all personal computers sits a microprocessor.
Microprocessors have basic characteristics:
Computational bandwidth: The number of bits processed in a single instruction.
Speed: Given in megahertz (MHz), the speed determines how many instructions per second the processor can execute.
Ответьте на вопрос
What is a microprocessor?