Английский язык. Арланова Т.Л - 7 стр.

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7
restrict - ___________________
pollute - ___________________
Exercise 3. Answer the questions:
1) What does the future of railways depend on? What's your opinion? 2) What
kind of traction - electric or diesel - results in the increase in the speed of
trains? 3) Does electric traction provide the improvement of labour conditions
? 4) Is the electric power supply system a costly business? 5) What types of
current do you know? What current is most often used in our everyday life? 6)
How do you think, is the high voltage of the substation lowered for
transmission over the railway network?
Exercise 4. Read the text and translate in into Russian.
RAILWAY ELECTRIFICATION
The key to the increase of train capacity in recent years has
undoubtedly been the impressive spread of electrification. Numerous studies
and tests as well as practical railway experience show that electric traction
has many advantages, especially on lines carrying high-density traffic. The
replacement of diesel traction by electric one leads to an all-round
improvement in the main operating parameters and the reduction in cost.
There is an increase in the average speed of trains, a useful increase in
traffic capacity., line capacity., increased automation and hi gher
productivity and a reduction of rolling stock requirements. Thus, as
compared to diesels, under average conditions, the use of eight-axle
electric locomotives results in the increase in the speed of trains by 15-25
per cent.
Undoubtedly, railway future lies in electrification. The conversion of
railways to electric traction provides the improvement of labour conditions,
the reduction ofair pollution the electrification of settlements situated along
the railway lines. Electric traction promotes the automation and
mechanization in track laying and repairs.
The reliability of electric traction is a function of combined reliability of the
locomotives and power supply, especially the overhead contact wire.
Along its whole length the track on which electric locomotives run must
have either an overhead contact wire {catenary) or an extra rail (third or
third and fourth rail) from which the train can continuously pick up power.
Overhead contact wire is connected with electrical substations and cables
to bring the power to the track. As to the extra rail, it is placed in the track
between the two running rails. This power supply system makes railway
electrification a costly business, therefore it is justified only on railways with a
high density of traffic. It should be noted, that the third rail system is
particularly essential for underground railways because of a limited space
available in tunnels.

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