ТОП 10:

II. Read the text and fill the gaps 1- 4 with an appropriate variant from A-E. One point is not used.



Computers have already turned into essentials for us. We can’t do without them ________ (1). There’s a strong opinion that computer technologies give new opportunities to people who study languages. At first glance it may sound strange – the computer is a lifeless object, ___________ (2)?

The main advantage of the computer is that it can make learning and drilling less boring. There are lots of computer games ___________ (3). Internet access provides learners with up-to-date news, and typing helps to remember word spelling.

Nowadays computers are able to teach speaking, too – there is special software that can check the position of the user’s lips and tongue, ________ (4).

No doubt, the computer will learn how to answer our questions and will become a skillful conversationalist.

 

A neither at work nor in the classroom

B because it can be useful for writing too

C and it can correct pronunciation mistakes

D which turn learning new words into fun

E how can it possibly develop our communication skills

 

III. Write an essay to the topic “Computers in the modern world”, using 150-200 words.

Unit III

Physics of colours

Warming-up discussion:

  • Name the colours of the rainbow.
  • What is your favourite colour?
  • Can you define warm and cold colours?
  • What colours do you prefer in clothes?
  • Name as many colours as you can.

KEY VOCABULARY

1. colour (color) - цвет

2. primary colour – основной цвет

3. hue – оттенок, тон

4. pigment – цветовой пигмент

5. to distinguish - различать

6. to derive – получать, извлекать

7. to define - определять

8. substance - вещество

9. to refract - преломлять

10. refrangibility - преломляемость

11. angle - угол

12. additive – аддитивный, добавленный

13. subtractive – субтрактивный, вычитаемый

14. retina – сетчатка глаз

15. rods – палочки (чувствительные элементы глаза)

16. cones – колбочки (чувствительные элементы глаза)

17. scotopic - скотопический, ночной (о зрении)

18. photopic – дневной

19. emission – выделение, распространение

20. reflection - отражение

21. to absorb - поглощать

22. to yield [jild] – давать результат, приводить к чему-либо

23. to devise – разрабатывать, изобретать

24. saturation - насыщенность

25. gloss - глянец

26. adjust – подгонять, регулировать

27. brightness - яркость

28. tertiary – относящийся к третьему разряду

29. trichromatic - трехцветный

30. to map -отображать

 

 

TEXT I: Physics of colours

The world is full of colours. Colour derives from the spectrum of light interacting in the human eye with special light receptors. Some researchers report that humans can distinguish about 16 million different colours. But what’s more interesting is that most of the colours we see around us and all the colours we see on TV or computer monitor can be created from just three different coloured lights.

How are all the colours made from just three different colours? Simply by combining the light in different rations. That’s it. Adjusting the brightness of three colours in different ways creates all the colours.

 

RGB and CMYK

 

On a microscopic level, the retina of a human eye is made up of two types of light sensitive cells, rods and cones. Rodes are best at scotopic or low-light-level night vision, while the cones are best at photopic or high-light-level, high resolution colour vision. Each retina has about 120 million rods, and 6 to 7 million cones, each is about 1 to 3 micrometer in diameter. The human eye has three types of cones which receive short (S) - blue, medium (M) - green and long (L) – red wavelengths. They are also known as the blue, green and red receptors. We see colours because these cones are stimulated.

Visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has a wavelength in the range of about 380 nm (nanometres) to about 740 nm – between the invisible infrared, with longer wavelengths and the invisible ultraviolet, with shorter wavelengths.

 

 

The additive primary colours are red, green and blue (RGB). Coloured lights are mixed using additive colour properties. Light colours are combining two or more additive colours together, that creates a lighter colour that is closer to white. Combining all three additive primary colours in equal amounts will produce the white colour. So, adding different colours creates white, and the absence of all light equaling black.

 

Additive colours combined in equal parts:

Blue + Green = Cyan

Red + Blue = Magenta

Green + Red = Yellow

Red + Green + Blue = White

 

By changing the brightness of each of the three primary colours, by varying degrees, you can make a wide range of colours.

 

Additive colours combined in unequal parts:

1 Green + 2 Red = Orange

1 Red + 2 Green = Lime

1 Green + 1 Blue + 4 Red = Brown

 

Computer monitors and televisions are an application of additive colours. These devices use a mosaic of red, green and blue dots. Our eyes do not distinguish the dots.

Look closely at a white spot on your computer monitor using a strong magnifying glass or eye loop. You should be able to see that the white dot isn’t really white, but rather is a combination of red, green, and blue dots all located very close to one another.

The distinction between additive and subtractive colours is based on a fact that the image is derived from a light source, like a TV set that uses glowing phosphorus, or reflected natural light, as from a book, photograph, wall or any other object.

It is possible to print colour pictures using just three colours of ink, but you have to work in reverse of the process of mixing light colors. We see light colours by the process of emission from the source. We see pigment colour by the process of reflection (light reflected off an object). The colours which are not reflected are absorbed (subtracted). The subtractive primary colours are cyan, magenta and yellow. These are three colours used in printer’ ink cartridges.

 

combine absorbs creates
Blue + Green Red Cyan
Red + Blue Green Magenta
Green + Red Blue Yellow

 

Subtractive colour mixing

combine absorbs leaves
Cyan + Magenta Red + Green Blue
Cyan + Yellow Red + Blue Green
Magenta + Yellow Green + Blue Red
Cyan + Magenta + Yellow Red + Green + Blue Black

 

According to the table above, combining all three subtractive pigments yield black. In practice it doesn’t yield really as true as black colour as printing with black directly. So, most colour printing is done with four ink colours: cyan, magenta, yellow and black, or CMYK for short, where “K” is used instead of “B” to avoid confusion with blue.

The Colour Science

The science of colour is sometimes called chromatics, chromatography, colorimetry, or simply colour science. It includes the perception of colour by the human eye and brain, the origin of colour in materials, colour theory in art, and the physics of electromagnetic radiation in the visible range (that is, what we commonly refer to simply as light). There are four main classes of instruments used in colorimetry: colorimeter, spectrophotometer, densitometer, and spectroradiometer. Colorimetry defines and measures colours in a way that will correlate to how an ”average” person will see the colour. It is needed in chemistry, colour printing, paint manufacturing, textile manufacturing and advertising.

This science has to be quite accurate, since people are said to be able to recognize over 16 million different colours. Defining and measuring colours is difficult since every person sees colour a little differently, because colour is a combination of the physical sensation of light and the individual psychological interpretation of it. That’s why, from 1931 the International Commission on Illumination (CIE - its French abbreviation for Commission internationale de l'éclairage) has devised a standardized technique for defining and measuring colour using the data for a standard observer. It developed a mathematical colour model, which mapped out the space of observable colours and assigned a set of three numbers to each.

Colour blindness

If one or more types of a person's colour-sensing cones are missing or less responsive than normal to incoming light, that person can distinguish fewer colours and is said to be colour deficient or colour blind (though this latter term can be misleading; almost all colour deficient individuals can distinguish at least some colours). Some kinds of colour deficiency are caused by anomalies in the number or nature of cones in the retina. Others are caused by neural anomalies in those parts of the brain where visual processing takes place.

Species that have colour receptors different from humans – such as bird species, which may have four receptors – can make colour discriminations that humans cannot. A color reproduction system "tuned" to a human with normal colour vision may give very inaccurate results for the other observers, human or non-human.

 

 







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