Методические указания и контрольные задания для студентов заочников

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1. During a year almost 200 million tons of metal objects are considered to be destroyed by corrosion. Considering that about 600 million tons of metal a year are produced in the world, it is easy to understand the losses of objects without which our life could not be imagined.

2. The situation is very serious, because not only metal is destroyed but also a great amount of articles, instruments and tools whose cost exceeds many times the cost of the metal used for their manufacture.

3. Combating against the corrosion of metals has now become a key problem in all industrialized countries.

The scientific and technical achievements in the field of raising the corrosion resistance of construction materials are the basis of technical progress in different branches of industry, an indicator of the country’s economic potential.

4. A large amount of “anti-corrosion” work is being carried out in Russia. The results are evident: Russian-made inhibitors, varnishes, paint covers are being well known throughout the world. Gas pipelines, metal structures, the bodies of atomic reactors and ships, etc. have been reliably protected against corrosion.

5. Russia also exports special equipment and some kind of technology designed to weaken corrosion. Anti-corrosion varnishes, paints, insulating materials and equipment are sold abroad.
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What materials weakening corrosion does Russia sell?

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1. The laser has become a multipurpose tool. It has caused a real revolution in technology.

Atoms emit rays of different length, which prevents the forming of an intense beam of light. The laser forces its atoms to emit rays having the same length and travelling in the same direction. The result is a narrow, extremely intense beam of light that spreads out very little and is therefore able to travel very great distances.

2. The most common laser is the helium-neon laser in the laser tube, containing 10 per cent helium gas and 90 per cent neon gas. At the end of the tube there is a mirror, and at the other end there is a partial mirror. The electrons get energy from a power supply and become “excited”, giving off energy as light. This light is reflected by the mirror at one end of the tube. It can only escape through the partial mirror at the other end of the tube.

3. The first laser was built in 1960. Since then scientists have developed several types of the laser which make use of luminescent crystals, luminescent glass, a mixture of various gases and finally semiconductors.

4. Having been developed at The Institute of Physics in 1962, semiconductor quantum generators occupy a special place among the optical generators. While the size of the ruby crystal laser comes to tens of centimeters and that of the gas generator is about a meter long, the semiconductor laser is a few tens of a millimeter long, the density of its radiation being hundreds of thousands of times greater than that of the best ruby laser.

5. But the most interesting thing about semiconductor laser is that it is able to transform electrical energy directly into light wave energy. The semiconductor laser opens up new possibilities of producing extremely economical sources of light.
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What possibilities does the semiconductor laser open?

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1. The first machine for mathematical computation was built in 1822 by the mathematician Charles Babbage. From the description of this machine we know him to understand clearly all the fundamental principles of modern digital computers. Babbage was born in England in 1792. He taught himself mathematics so well that when he went to Cambridge he found that he knew algebra better than his teacher. Babbage constructed a model of a computer and devoted the rest of his life to developing an universal computing machine. But he was not understood by his contemporaries.

2. Two generations of engineers worked hard to construct a modern computer. Their attempts resulted in the development of computing machines which transformed the whole course of scientific achievements. If you looked at the machines which people had used up to 1946, you would notice that they were not so perfect as the ones available today.

3. Having invented computers engineers began to use them in industrial automatic processes. They are known to carry out several thousand arithmetic operation in one second. If there had been no computers space flights and many other achievements of modern science and technology would have been impossible.

4. We often hear that the increasing flood of information will be one of the problems of the 21-st century. The computers may help to solve it too.

5. As the electronic computer has opened great prospects for further development of science and technology, it may be spoken of as one of the most important inventions of our time.

Why may a computer be spoken of as one of the most important inventions of our time?

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1. Not long ago computers were not very reliable and comparatively slow in operation. Since then, several generations of complex electronic computing equipment have been developed, each being significantly better than the one before it. Almost every day a new use is found for these astonishing devices to help men.

2. We know a computer to be a complex electronic device that can store and process vast quantities of information. Following instructions, computing equipment will perform calculations such as addition, subtraction, multiplication and division and provide the answers to a large variety of problems in a tiny fraction of time¹. A computer is known to be the “heart” of an electronic data processing system², other parts of equipment being auxiliary.

3. There are two types of computing equipment – digital³ and analogue. They work differently and yield different results. The digital computer is performing a much broader range of functions than the analogue.

4. The analogue computer produces analogues or parallels of the process to be described or the problem to be solved. Both digital and analogue computers must be programmed. This means they must be set up in such a way that they can produce a result from the information fed into them and the information itself must be organized so that it can be handled by the machines. These devices working by electronic impulses perform at fantastic speed and with great precision.

5. Nowadays computer makers are working at the problem of introducing small computers into our life.

What problem are computer makers working at nowadays?

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