Who discovered electricity?

The story of the discovery of electricity is connected with the name of Thales, the Greek philosopher. The story goes that one day Thales rubbed a piece of amber against his sleeve and found to his great surprise that it attracted small bits of dried leaves. After further experimenting he concluded that this attractive force was a property that amber alone possessed. He called this characteristic “electricity”because the Greek word for amber was electron.Thales' great discovery remained a curiosity for more than two thousand years. Then many other substances were found to have this curious property of electricity too. Naturally the people of the past had no idea of what electricity was. They thought of it as”rays” or “stream” that passed from the rubbed material. There were scientists who thought electricity to be a sort of “fluid” that flowed through wires as water flows through pipes. Later many of them found out that electricity was made of tiny particles of some kind. In this way they tried to separate electricity into individual particles. There were some attempts to weigh a single particle of electricity and calculate its electric charge. This was one of the most delicate weighing jobs ever done by a man, for a single electric particle weighs only about half a millionth of a millionth of a millionth of a millionth of a millionth of a pound. To make up a pound, it would take more of those particles than there are drops of water in the Atlantic Ocean. Now we know these electric particles to be electrons.

When a large number of electrons break away from their atoms and move through the wire, we describe this action by saying that electricity is flowing through the wire and the electrical ” fluid” that scientists of the past talked about is nothing else than electrons flowing along a wire. A lot of scientists worked in the field of electricity doing their best to make the life of people good and happy.

Вопросы к тексту:

1. What did Thales, the Greek philosopher, notice once?

2. What did Thales call that property of amber?

3. What is the Greek word for amber?

4. What did people think of electricity?

Задание №2 Переведите следующие слова и словосочетания: to rub, amber, to attract, bit, attempt, to remain, the attractive force, a property, to flow through the wire, a single particle of electricity, tiny, curious, to weigh.

Вариант№6

Задание № 1.Переведите текст и письменно ответьте на вопросы к нему:

" Moscow Metro."

In 1931 it was decided to start preparations for the building of the Metro in Moscow. In the spring of 1932 the project drawn up by Soviet engineers and architects was endorsed. Thousans of young specialists and mine workers, construction workers from the Donbas and from Moscow region, from the Urals, and Dneprostroi went undeground into Metro shaffts and tunnels.In a short time (it was called a record time by the world press) the first line was cinstructed. More than eleven kilometers of track connected the Sokolniki district with the Gorky Park district. There were ten stations on this line. The construction work was done in difficult geological conditions, of a kind never encountered by European or American Metro builders. So this day saw the first section of a double track line 8 miles long put into operation. The Metro was opened on May 15, 1935.Since then building work on the Metro has not stopped for a single day. Even at the time when the fascist hordes were near Moscow, the Metro builders continued their work. After the war the scale of construction increased considerably. The construction of the belt line was completed and it connected all the radial routes. The new routes and stations began appearing in new housing districts. Some of the lines go overland, across new bridges and aqueducts. Moscow's rapidly increasing population, the growth of its industrial enterprises and cultural institutions required the capital to have efficient and convenient means for accommodating passenger traffic. The people of our country wanted the Metro to be the best in the world. There are many stations in the Metro; their surface buildings and underground halls are spacious, well ventilated and well lit. They differ widely in architectural design and are decorated with marble, bronze, aluminum and glass. The present Metro coaches are much better than the early ones. They are considerably lighter in weight, and the seats are soft. Muscovites and the visitors to the city do not have to wait long for trains, for the interval between them is always short. “Clever” machines have appeared in the Metro recently. An experimental automatic driver conducts trains according to the time-table and stops precisely as required. The Moscow Metro is developing rapidly. The capital is growing, and Metro lines are being constructed every year.

Вопросы к тексту:

1) When was it decided to start the building of Moscow Metro?

2) By whom was the Moscow Metro built?

3) When was the Moscow Metro opened?

4) Why is this metro so important for our capital?

Задание №2 Переведите следующие слова и словосочетания на русский язык:

to develop rapidly, lines of the Moscow Metro, an automatic driver, according to the time-table, to be considerably in weight, a double-track line, mine workers, passenger traffic, to be well ventilated and lit, metro builders, the growth of enterprises, to be decorated with marble.

Вариант №7

Задание №1 Переведите текст и письменно ответьте на вопросы к нему.

“Thermal electrical plants.”

Hydroelectric stations deliver power from great rivers, but still about 80 per cent of the required electric power is produced in thermal electrical plants. These plants burn coal, gas, peat or shale to make steam.To understand how the energy of fuel is converted into electrical energy let us discuss the heat process and begin with the fuel.

Gas is delivered through gas pipelines. The coal (peat, shale) arrives in trains, and conveyors or cranes unload it for storage and bring it to the furnace. It is more effective to burn coal in the form of powder, therefore it is first crushed, pulverized and blown into furnaces. To attain complete combustion of the powder a large volume of air is needed, delivered by forced air fans, exhauster fans and smoke stacks. The steam boilers or steam generators supply the huge amount of high-pressure, high-temperature steam required to drive the high-power turbine-generators.

The kinetic energy of its steam acts against the blades of the turbine and rotates its shaft joined to the generators shaft.A centralized control desk with panels and many instruments and automatic control devices supervises and monitors the plant, with only a few operators.

Вопросы к тексту:

1. Where are hydroelectric stations located?

2. What does the kinetic energy of the steam do with the blades of the turbine?

3. What does a centralized control desk to?

4. Why are there only a few operators at such electrical plants?

Задание № 2. Переведите следующие слова и словосочетания:

to require, to convert, fuel, to deliver through pipelines, to supply, the generator shaft, a centralized control desk, to drive the high-power turbine generators, to monitor, to feed, fans, combustion, power input, raw materials, voltage transformer, high-pressure.

Вариант №8

Задание№1. Переведите текст и письменно ответьте на вопросы к нему.

“Freight cars”

Nearly all of us known more about passenger train cars and passenger trains that we know about freight train cars and freight trains, since we have all ridden on passenger trains while a great many of us have never had anything to do with shipping goods on freight cars. The cars on a freight train are known to be seldom alike, they are usually of many types and sizes, special kinds of freight requiring special kinds of cars. But nowadays one can see the so-called bulk trains, that is, trains consisting of wagons of one type only for regular transporting large quantities of goods from one place to another. All world railways have several classes of commonly used cars and there are usually several kinds of cars in each class.

One of the most widely used cars is the cars is the car for transporting coal from mines. This car is called an open-top car, for it has no roof. There are two types of open-top cars, the hopper and gondola car, the latter having a flat floor or bottom. The former, i.e. the hopper car, has a floor sloping downward from each end and in some cars from the sides also. The amount of freight to be carried depends upon the size of the floor space and the height of the sides and ends of the car to be used. Therefore we distinguish low-sided and high-sided wagons as well as low –capacity or high-capacity ones. Both hoppers and gondolas are used to carry stone, gravel, crushed rock and other bulky materials which may be exposed to weather.

A type of car that is not very old but has become very popular is the covered hopper car. It looks like a conventional hopper but it is roofed. To load or fill the car you use water-tight hatches in its roof and you empty or unload it through its hopper bottom. It is much cheaper to carry bulky materials that cannot be exposed to weather such as cement, dry powdered chemicals, etc., in these cars than to place them in bags and ship the bags in special cars.

Вопросы к тексту:

1) For what are special types of cars required?

2) What is the most widely used type of freight cars?

3) For what are hoppers and gondolas used?

4) What type of cars has become very popular?

Задание №2. Переведите следующие словосочетания на русский язык:

wheelbase, brakes, emergency, partition, for passing with safety, by making the trucks very strong, the absence of signaling, the danger of travelling, the car lighting and heating systems, the most uncomfortable car seats, the fastest way of transportation.

Вариант №9