Write out of paragraphs 3-6 words and word combinations describing the creation and broadcasting a television program. Use them for rendering to your group-mates.
6. Define the forms and functions of Gerund:
1) Studying small structures is accomplished with the help of microscope.
2) Scientists began working at the problem of magnifying the power of microscopes more than 200 years ago.
3) They were greatly interested in improving the lenses.
4) Adding heat to a substance will not always cause a rise of its temperature.
5) The sound effect of increasing the magnet current is to increase the field strength at every point.
6) Representing the electric field by means of these lines help us to picture the forces between the changed bodies.
7) The experiments of physicists resulted in making much more powerful microscopes.
8) The main point of a transformer is changing voltage although the power of both sides of the transformer is equal.
9) After introducing new technology in that branch of industry some changes must be made as soon as possible.
10) The necessity in the form of increasing productivity gave birth to new automatic mechanism.
11) On reading J. Von Neumann's paper we understood the main idea of internal memory for storing the program.
12) By using transistor circuits scientists removed size limitation of the previous computers.
13) Measuring temperature is necessary in many experiments.
14) The laser beam is made exciting the atoms of a suitable material.
15) There can be no progress in science without experimenting.
16) Upon adding heat we can change the state of a substance.
17) Penetrating into space was very important for mankind.
18) For many centuries men were interested in obtaining new sources of energy.
19) When atoms or molecules are excited they emit electromagnetic waves. By counting the number of waves in certain period, a very accurate measure of time can be defined.
20) Telemetry is the science of seeing some place without being there.
Define whether the word with the suffix -ing is a Verbal noun, a Gerund or a Participle:
1) Our aim is solving this complex problem.
2) They succeeded in obtaining good results working with this metal.
3) The building of this laboratory will be finished next month.
4) In testing the devices they found some serious faults.
5) The growing importance of automatic equipment in industry attracts world-wide attention.
6) These scientists played a great role in the spreading of the metric system.
7) After graduating from Petersburg University A.S. Popov remained there as a post-graduate at the Physics Department.
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8) After Hertz had published his experiments proving the existence of electromagnetic waves, A.S. Popov thought of a possibility of using Hertz waves for transmitting signals over a distance.
9) On March 24, 1896 he demonstrated the transmission and reception of a radiogram consisting of two words: Heinrich Hertz.
10) Using the new method it is possible to increase accuracy and speed of spectral analysis.
Thousands of scientists, using the most modern equipment, are studying the atmosphere.
Lesson Two
I. Pre-text Exercise
1. Learn the meaning and pronunciation of the following words:
surveillance [sə:'veiləns], identification [aiِِِِِِ¸dentifi'keiʃn], echo ['ekou], visualize ['vizjuəlaiz], barrage ['bæra:ʒ], compass ['kΛmpəs], anchor ['æŋkə], guide [gaid], sign-posts ['sainpousts], height [hait].
Read and remember the Plural of the following Nouns.
phenomenon [fі'nɔminən] - phenomena [fі'nɔminə]
symposium [sim'pouzjəm] - symposia [sim'pouzjə]
spectrum ['spektrəm] - spectra ['spektrə]
momentum [mou'mentəm] - momenta [mou'mentə]
II. Read the following text carefully.
While you are reading look for the answers to the questions:
1. How many categories are the uses of radar generally divided?
2. What are the ways of radar working?
3. What peaceful purposes is radar used today for?
Text В
How radar works
1. The design of a radar begins with consideration of its intended use, that is, the function to be performed by the radar as a whole. The uses generally divide into three categories:
1) Warning and surveillance of activity, including identification.
2) Aids to the direction of weapons, that is, gunfire control and searchlight control.
3) Observation of terrain echoes or beacons for navigation and control of bombing.
2. There is nothing mysterious or complex about radiolocation. It rests on the foundations of ordinary radio theory, and is a technique based on the transmission, reception, and interpretation of radiofrequency pulses. Considered as a whole, it must be admitted that even the most elementary of radar equipment is difficult to visualize, but thus us simply due to the fact that so many (normally) curious circuits and pieces of apparatus are gathered together under one roof. No particular circuit or detail of the equipment is in itself especially difficult to understand, and once the elements are known the complete assembly is no longer mentally unmanageable.
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3. The word "radar" is derived from the phrase "radio direction-finding and range", and it may be more expressive than the older "radiolocation", or it may not. Finding the position of an aircraft or a ship by means of radio covers a very wide field of electronic application; covers, in fact, the whole area of radio direction-finding (R.D.F.) from the elementary bearing-loop to the principle of the reflected pulse which represents the latest principle of the technique. In this article the term will be used to cover only those methods of detection, which depend upon the reflected pulse, the characteristic (by popular opinion) which distinguishes radar from all other methods of position finding in that no co-operation is required on the part of the target. We shall not dwell, therefore, upon the older and more familiar methods, which depend upon the reception at two or more points of a signal, transmitted by the body under location itself.
4. The actual equipments in use which employ the reflected pulse principle are greatly varied from the point of view of physical appearance, but their basic principles are the same.
5. First, let us tabulate and briefly analyze the problem to be met. The aim of radar is to find the position of a target with respect to a fixed point on the ground - say the position of an aeroplane or a barrage balloon with respect to the radar equipment situated in a field a mile or so away. Three quantities must be measured in order to define the position of the aeroplane or the barrage balloon: first, the slant range, the length of the most direct line drawn from the radar site to the target; second, the angle of bearing, i.e. which point of the compass the target occupies; third, the angle of elevation. When the target is an aeroplane, these three quantities are continuously varying so that the problem of position finding is somewhat complicated by the fact that the radar equipment has to "follow" as well as find. In the case of barrage balloon, things are not quite so difficult, and the three important factors may be found at leisure.
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6. Radar works in this way. Powerful transmitters send out a stream of radio-waves, called "pulses", at the rate of perhaps - one thousand every second. These pulses shoot through the air at a speed of one hundred and eighty-six-thousand miles a second till they hit an object, perhaps a ship, an aeroplane, an iceberg or a hill. These pulses cannot go through the object; and so they immediately shoot back at the same speed, in the opposite direction, and hit the aerial of the radar. The moment this happens, a spot or line of light appears on the radar screen, showing the position and distance of the object.
7. Today radar is used for many peaceful purposes all over the world. Modern ships of all nations carry radar to help them sail in bad weather, when it is possible to see for a distance of perhaps only a few hundreds yards. In the past, the captain usually had to anchor his ship at such times and wait for conditions to improve. But today a ship with radar can sail in almost any weather conditions, with no danger of an accident.
8. Radar also helps to guide aeroplanes across the world. Radio signals called beams are transmitted into the sky from land radio stations at a number of points along their course. The pilots can hear these signals on their radio and see them on their radar screen. The beams are like sign-posts in the sky. A pilot guides his aeroplane towards one beam, and then flies on to the next beam. At the end of his journey, he will land his aeroplane with the help of radar. Trained men at the airport watch the aeroplane on their radar screens and tell the pilot by radio the course to follow, they tell him when and by how much to reduce height, and give any other orders that may be necessary.
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9. In many countries radar controls the speed of cars on roads where there is a speed limit. They hope that radar will help them reduce the number of accidents on the roads. Thousands of people all over the world lose their lives in road accidents every year. The police can now watch the speed of the cars on their radar screens and stop motorists from driving too fast.
10. Radar is used to forecast the weather, and to study the moon and stars. Powerful radar telescopes are used to study the stars. They are also used to study scientific experiments in space.
III. After-text Exercise
1. Agree or disagree with the next statements:
1) Radiolocation rests on the foundations of ordinary radio theory, and is a technique based on the transmission, reception and interpretation of radiofrequency pulses.
2) The aim of radar is to find a position of a target without respect to a fixed point on the ground.
3) Powerful transmitters send out a stream of radio-waves, called "pulses". These pulses can go through the object.
4) Radio signals called beams are transmitted into the sky from land radio stations at a number of points along aeroplanes course.
5) Powerful radar telescopes are used to study the stars.
2. Find the Information about:
1) finding the position of an aircraft or a ship by means of radio;
2) three quantities which must be measured in order to define the position of an aeroplane or the barrage balloon; 3)using radar by modem ships;
4) guiding aeroplanes by means of radar;
5) other peaceful uses of radar.
Put questions to each other.
4. Summarize the general ideas of text Use the following plan:
1) The beginning of the design of a radar.
2) The most elementary radar equipment.
3) The aim of a radar.
4) The principles of radar working.
5) Peaceful purposes of a radar.
5. Translate the following sentences paving attention to the Gerundial Construction:
l) We know of copper having been used as a conductor owing to its suitable characteristics.
2) He objected to the goods being paid in advance.
3) We insisted on their being offered favorable terms of payment.
4) There is no hope of our getting a complete analysis of the measurements within 10 days.
5) The scientist insisted on the speed of computation being increased.
6) We didn't know of their having worked in the field of computing.
7) There is a probability of our being sent to the conference.
8) There is a probability of his being appointed chief engineer at our plant.
9) Our going there now won't help much.
10) The semiconductor diode being very important device of modem science and industry is common knowledge.
11) The semiconductor diodes having many important characteristics resulted in their being used in different branches of industry.
12) We know of copper, silver, aluminium and many other metals being good conductors of electricity.
13) The reliable functioning of television depends on the television set being equipped with semiconductors.
14) Benjamin Franklin's having invented the first lightning conductor is a well established fact.
15) We were told about their having studied a number of problems connected with the development of computing machinery.
16) Kurchatov's having devoted all his life to nuclear physics is known to everybody.
17) I know of their being shown the new device.
18) We know of the Curies' having discovered some new radioactive elements.
19) I have heard of their experiment being successfully completed in the nearest future.
20) We know of Rutherford's having investigated the nature of alpha-particles.
6. Translate the following sentences. Define whether Gerund or Verbal Noun is used:
l) The performing of operations is very quick.
2) Pascal's having designed his elementary adding machine in 1642 helped Leibniz develop the first machine to multiply and divide directly.
3) Computers also perform calculations in finding solutions to complex scientific problems.
4) The coding of instructions is done by the operator.
5) The compiling of the program is performed by the programming engineer.
6) In the digital computer the method of representing numbers and all other information is based on the use of binary digits (bits) which are represented by electronic signals.
7) 100 years ahead of this time Babbage succeeded in planning an analytic engine that had all the major features of a modern computer.
8) This is only the indication of the time saving available in the computer field.
9) Our definition of thing implies the entrance of an idea into one's mind with or without deliberate consideration of reflection.
10) The magnetism induced in the armature of the coil attracts a ferrite piece on the end of the relay spring and causes the mechanical opening or closing of the switch contacts point.
11) The characteristics of switching networks are useful for designing computers.
12) We shall discuss input and output services for converting the information on coded cards to a form suitable for storage in the internal memory.
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