1. Read the text once more, complete the questions and answer them




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1. Read the text once more, complete the questions and answer them:

1) What is an early______ of elecricity?

2) How does the light bulb ____________ by?

3) Is electricity __________ form of energy?

4) Whose ________ is clean?

5) When was __________ light bulb invented?

6) Where does the ______ effect see more direct use?

7) Where was the use of electric heating ______?

8) What was demonstrated in _______?

9) Does the ________ bring danger?

10) What is the most _______ of the 20-th century in the field of electricity?



The light bulb, an early application of electricity, operates by Joule heating: the passage of current through resistance generating heat.

Electricity is an extremely flexible form of energy, and it may be adapted to a huge and growing number of uses. Historically, the growth rate for electricity demand has outstripped that for other forms of energy, such as coal. While debate can be expected to continue over the environmental impact of different means of electricity production, its final form is relatively clean.

The invention of a practical incandescent light bulb in the 1870s led to lighting becoming one of the first publicly available applications of electrical power. Although electrification brought with it its own dangers, replacing the naked flames of gas lighting greatly reduced fire hazards within homes and factories. Public utilities were set up in many cities targeting the burgeoning market for electrical lighting.

The Joule heating effect employed in the light bulb also sees more direct use in electric heating. While this is versatile and controllable, it can be seen as wasteful, since most electrical generation has already required the production of heat at a power station. A number of countries, such as Denmark, have issued legislature restricting or banning the use of electric heating in new buildings. Electricity is however the only practical energy source for refrigeration, with air conditioning representing a growing sector for electricity demand, the effects of which electricity utilities are increasingly obliged to accommodate.

Electricity is used within telecommunications, and indeed the electrical telegraph, demonstrated commercially in 1837 by Cooke and Wheatstone, was one of its earliest applications. With the construction of first intercontinental, and then transatlantic, telegraph systems in the 1860s, electricity had enabled communications in minutes across the globe. Optical fibre and satellite communication technology have taken a share of the market for communications systems, but electricity can be expected to remain an essential part of the process.

The effects of electromagnetism are most visibly employed in the electric motor, which provides a clean and efficient means of motive power. A stationary motor such as a winch is easily provided with a supply of power, but a motor that moves with its application, such as an electric vehicle, is obliged to either carry along a power source such as a battery, or by to collect current from a sliding contact such as the pantograph.

Electronic devices make use of the transistor, perhaps one of the most important inventions of the twentieth century, and a fundamental building block of all modern circuitry. A modern integrated circuit may contain several billion miniaturised transistors in a region only a few centimetres square.

2. Make up the questions using these words:

1) When muscles will contract?

2) Greek What word mean does piezein?

3) you What will a burn do you when get?

4) has execution become What rarer as recent judicial in time?


5) is nature in What several forms observed in?

3. Make up 2 questions to the text.


Structure of electricity networks


The structure, or "topology" of a grid can vary considerably. The physical layout is often forced by what land is available and its geology. The logical topology can vary depending on the constraints of budget, requirements for system reliability, and the load and generation characteristics. The cheapest and simplest topology for a distribution or transmission grid is a radial structure. This is a tree shape where power from a large supply radiates out into progressively lower voltage lines until the destination homes and businesses are reached. Most transmission grids require the reliability that more complex mesh networks provide. If one were to imagine running redundant lines between each limb and branch of a tree that could be turned in case any particular limb of the tree were severed, then this image approximates how a mesh system operates.


4. Translate the sentences from Russian into English:

4) В сети выделяют линии электропередачи, которые соединяют подстанции.

5) К подстанциям, как правило, подходит несколько линий.

6) Внутри подстанции происходит преобразование напряжения и распределение потоков электроэнергии между подходящими линиями.

7) Для соединения линий и оборудования внутри подстанций используются электрические коммутаторы различных типов.

8) Потери энергии в линиях обратно пропорциональны напряжению, поэтому для снижения потерь электроэнергию выгодно передавать на высоких напряжениях.

10) Структура сети также может быть изменена для оптимизации электрического режима сети

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