Computers have already turned into essentials for us. We cant do without them ________ (1). Theres 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 users 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) -
2. primary colour
3. hue ,
4. pigment
5. to distinguish -
6. to derive ,
7. to define -
8. substance -
9. to refract -
10. refrangibility -
11. angle -
12. additive ,
13. subtractive ,
14. retina
15. rods ( )
16. cones ( )
17. scotopic - , ( )
18. photopic
19. emission ,
20. reflection -
21. to absorb -
22. to yield [jild] , -
23. to devise ,
24. saturation -
25. gloss -
26. adjust ,
27. brightness -
28. tertiary
29. trichromatic -
30. to map -
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 whats 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. Thats it. Adjusting the brightness of three colours in different ways creates all the colours.
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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 isnt 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 |
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According to the table above, combining all three subtractive pigments yield black. In practice it doesnt 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. Thats 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.
Text II: History of colour theory
History of colours dates back to the ancient Greek philosophical texts written in dialogues by Plato and Timaeus (390BC), passages in writing of Aristotle (350BC) and De Coloribus (330BC). In that study of colour the interests of artistic painters and their understanding of the behavior of light and colour were taken as a basis.
According to the old colour mixing theory the simple or primary colours were white and black or light and dark. From this primaries the noble hues of red, yellow and blue were mysteriously derived. By mixing the noble hues, the ancient artists got the composite hues of orange (gold), green and purple.
In 1390, Cennino Cennini published a description of how artists worked with colour. He described seven colours. Four (black, red, yellow and green) were mineral in character. Three more - lime white, the blues (ultramarine, lapis lazuli and azurite) and orange were colours which needed to be developed artificially.
In the visual arts, colour theory is a body of practical guidance to colour mixing and the visual impacts of specific colour combination. There are also categories of colours based on the colour wheel: primary colour, secondary colour and tertiary colour. Although colour theory principles first appeared in the writings of Leone Battista Alberti (1435) and the notebooks of Leonardo da Vinci (1490). The tradition of "colory theory" began in the 18th century, initially within a partisan controversy around Isaac Newton's theory of colour and the nature of so-called primary colours.
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In 1704, Sir Isaac Newton published his Opticks, which made several points about colour. He said that the source of colour was not substances, but light. He demonstrated that the different colours of the spectrum result from light being refracted. He called this attribute of light refrangibility from the Latin word refringere which means the ability to be refracted. He distinguished that each colour had a specific angle of refraction, when light passes through a prism of lens. He argued that orange or violet light were just as primitive as red and yellow because they cannot be broken down farther into more basic colour. He identified seven primary colours in this order: red, orange, yellow, green, blue, indigo, violet.
Newton saw the colour spectrum as a close system. He attached the red starting point to the violet end point and made a circle of colourswhere the red and violet overlapped and added the colours of magenta and puple which did not appear in the color spectrum. There was no black and white in the circle, but the center was white, which corresponded to the result of mixing all light colours together. But Newton did not understand the difference between additive and subtractive colour mixing. The knowlege of this is directly connected with the special structure of a human eye, which was discovered later after Newtons reseaches.
In 1810, Goethe published his comprehensive Theory of Colours in which he described the physiological effects of colour.
In 1801 Thomas Young proposed his trichromatic theory, based on the observation that any colour could be matched with a combination of three lights. This theory was later refined by Jame Clerk Maxwell and Hermann von Helmholtz. Newton's law of mixture were experimentally confirmed by Maxwell in 1856.
At the same time as Helmholtz, Ewald Hering developed the opponent process theory of colour, noting that colour blindness and afterimages typically come in opponent pairs (red-green, blue-orange, yellow-purple, and black-white). Ultimately these two theories were synthesized in 1957 by Hurvich and Jameson, who showed that retinal processing corresponds to the trichromatic theory.
ACTIVITIES:
Exercise 1: Answer the following questions:
- What is colour?
- How are the colours created?
- Who developed the colour theory?
- How did people in the ancient time understand the colour?
- What inventions in the colour theory were made by Sir Isaac Newton?
- Describe the structure of a human eye.
- What is the range of the visible light wavelength?
- How is the colour created in the electronic devices?
- Give the definition of RGB and CMYK.
- What happens when one or more types of a person's colour-sensing cones are missing or less responsive?
Exercise 2: Find the English equivalent to the Russian word:
1) :
a) light
b) brightness
c) colour
2) :
a) rods
b) cones
c) retina
3) :
a) source
b) science
c) device
4) :
a) visible
b) invisible
c) colour-sensing
5) :
a) to refract
b) to reflect
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c) to react
6) :
a) colour blindness
b) colour separation
c) colour definition
7) :
a)regulation
b) refraction
c) recombination
8) :
a) trichromatic
b) trigonometric
c) triadic
9) :
a) chemise
b) chemistry
c) chemisette
10) :
a) develop
b) distinguish
c) discover
Exercise 3: Match a scientist with his biographical facts:
| Plato (427 BC-348 BC) | A | A Greek Pythagorean philosopher, features in Platos dialogues, where he is said to come from Locri in Italy. He is credited with lost work On the Soul of the Universe, although all ancient references to him derived from Plato and he may be a fictional character invented for the dialogues | |
| Timaeus (420 BC-380 BC) | B | An English physicist, mathematician, astronomer, natural philosopher. He described universal gravitation and the three laws of motion. He built the first practical reflecting telescope and developed a theory of color based on the observation that a prism decomposes white light into the many colours that form the visible spectrum. | |
| Aristotle (384 BC-322 BC) | C | A German writer, artist and politician. His work includes epic, lyric poetry, prose and verse dramas, memoirs, an autobiography, literary and aesthetic criticism; treatises on botany, anatomy, and colour. | |
| Leonardo da Vinci (1452-1519) | D | A Classical Greek philosopher, mathematician, student of Socrates, writer of philosophical dialogues, and founder of the academy in Athens | |
| Isaac Newton (1642 -1727) | E | An English polymath. He is famous for deciphering Egyptian hieroglyphics. He made notable scientific contributions to the field of vision, light, solid mechanics, energy, physiology, language, musical harmony and Egyptology. | |
| Johann Wolfgang von Goethe (1749-1832) | F | A German physician and physicist who made significant contributions to several areas of modern science. He is known for his mathematics of eye, theories of vision, ideas on the visual perception of space, color vision research, and on the sensation of tone, sound and empiricism. | |
| Thomas Young (1773-1829) | G | A German physiologist who did much research into colour vision and spatial perception. He proposed opponent colour theory in 1892. He disagreed with Thomas Young and Herman von Helmholtz. | |
| James Clerk Maxwell (1831-1879) | H | A Greek philosopher and polymath, a student of Plato and teacher of Alexander the Great. Together with Plato and Socrates he is one of the most important founding figures in Western philosophy. | |
| Herman Ludwig Ferdinand von Helmholtz (1821-1894) | I | A Scottish mathematical physicist. He formulated classical electromagnetic theory. He considered being one of the greatest physicists of all times, behind only Newton and Einstein. | |
| Karl Ewald Konstantin Hering (1834-1918) | J | An Italian Renaissance polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist and writer. |
Exercise 4: Complete the sentences with correct endings:
1. Some researchers report that humans can distinguish about:
a) 10 million different colours;
b) 16 million different colours;
c) 1 million different colous.
2. Most of the colours we see around us and all the colours we see on TV or computer monitor can be created from:
a) four different coloured lights;
b) seven different coloued lights;
c) three different coloured lights.
3. The human eye has three types of cones which receive:
a) ultraviolet wavelengths;
b) short, medium, and long wavelengths;
c) infrared wavelengths.
4. The additive primary colours are:
a) black and white;
b) cyan, magenta and yellow;
c) red, green and blue.
5. Colour blind person can distinguish:
a) fewer colours;
b) more colours;
c) no colours.
Exercise 5: Fill in the gaps, using the words from the box:
| electromagnetic spectrum, additive primaries, colour, printing inks, imaging, infrared, subtractive primary, ultraviolet |
- .. is a combination of the physical sensation of light and the psychological interpretation of it.
- The three colours red, green and blue are called . ...
- When an additive primary colour is taken away from white light, the remaining colours form a new color which is called .. .
- RGB are the colours used in ..
- CMYK are the system of colours, using in . .
- Light is the visible portion of the of the radiant energy.
- The invisible rays vary lower than 380 nanometers are called .
- The invisible rays border further 740 nanometers are
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Exercise 6: Put the sentences into appropriate Perfect tenses:
- I already (to see) during the experiment that colour derives from the spectrum of light.
- I never (to think) that we see colours because of the cones stimulation.
- We (to read) that history of colours (to date back) to the ancient Greek philosophical texts.
4. It was mentioned that a colour-blind reproduction system (to give) very inaccurate results for the other observers, human or non-human.
5. Newton (to identify) seven primary colours before he (to publish) his book Opticks.
6. You (to read) any philosophical texts about colours?
7. We arrived at work in the morning and found that somebody (to break) into the laboratory during the night.
8. At first, I thought I (to do) the experiment well, but I soon realised that I (to make) a big mistake.
Exercise 7: Match the term with the definition:
| Light | A | To take a number or amount from another number or amount. The symbol for this is -a minus sign. | |
| Colour | B | A part at the back of human eye that sends light signals to the brain, where they are changed into images. | |
| Spectrum | C | Inability to see the difference between some colours, especially red and green, because of a medical condition. | |
| Retina | D | To put numbers or amounts together to calculate their total. | |
| Nanometer | E | The complete range of colors into which light can be separated when it passes through a prism. | |
| Colour blindness | F | Brightness from the sun or from a light source (electrical equipment, candle, etc), which allows us to see things. | |
| To add | G | The quality of being red, green, yellow etc. | |
| To subtract | H | A unite for measuring length in the metric system. There are one billion (=one thousand million) nanometers in a millimeter. |
Exercise 8: Translate into Russian:
- A deep shade of red
- A delicate pink tone
- Reddish hair
- Dark green trousers
- Lovely deep blue eyes
- Rich brown velvet
- The men were wearing somber suits and black ties
- Bright yellow paint
- Curtains in vibrant shades of red
- He tends to wear silk shirts and loud ties.
- Look at those gaudy purple sunglasses
- Garish reds and bright yellows
- Pale gray feathers
- Light colors work best in north-facing rooms.
- She often wears pastels.
- Faded blue jeans.
Exercise 9: Read and act out the dialogue:
Speaker 1: -What is a rainbow?
Speaker 2: - I think its one of the most spectacular light shows observed on earth. Indeed the traditional rainbow is sunlight spread out into itsspectrum of colours and diverted to the eye of the observer by water droplets.
Speaker 1: -Why does the rainbow bow?
Speaker 2: -Really, this shape of rainbow describes the fact that the rainbow is a group of nearly circular arcs of thecolour all having a common center.
Speaker 1: -What makes the bow?
Speaker 2: -Well, we see the formations of a rainbow by raindrops. Its a problem in optics that was first clearly discussed by Rene Descartes in 1637. The bow appears not only in the sky, but also in the air near us, whenever there are drops of water illuminated by the sun, as we can see in some fountains. The rays of light act on these drops and pass from them to our eyes.
Speaker 1: -Why dont we see a full circle?
Speaker 2: -Oh, thats because the earth gets in the way. The lower the sun is to horizon, the more of the circle we see right at the sunset; we would see a full semicircle of the rainbow with the top of the arc 42 degree above the horizon. The higher the sun is, the smaller is the arc of the rainbow above the horizon.
Speaker 1: -Whatmakes the colours in the rainbow?
Speaker 2: -The traditional description of the rainbow is that it is made up of seven colours red, orange, yellow, green, blue, indigo, violet. Actually, the rainbow is a whole continuum of colours from red to violet and even beyond the colours that the eyes can see. The colours of the rainbow arise from two basic facts: first, sunlight is made up of the whole range of colours that the eye can defect; second, light of different colour is refracted by different amounts when it passes from one medium (for example, air) into another (water or glass).
Speaker 1: - What is the rainbows distance?
Speaker 2: -Well, it is nearby of far away, according to where the raindrops are.
Speaker 1: -And, do you know any proverbs or saying about rainbow?
Speaker 2: -Let me think
Rainbow at night, shepherds delight.
Rainbow in morning, shepherds take warning
If there be a rainbow in the eve,
It will rain and leave;
But if there be a rainbow in the morrow
It will neither lend nor borrow
Exercise 10: Write a list of colours
Grammar review:
Present Perfect
:
- , . , :
I have seen this film and I think it is dull. , .
Ann has read this book already. .
- , , :
I have been to the cinema twice this week. .
- , , :
I have known him all my life. .
He has always been in love with her. .
() : have/has + Participle II (v3):
| I You have seen We They | I You have not seen We They | Have I seen? we you they |
| He She has seen It | He She has not seen It | Has he seen? she it |
I have = Ive
He has = hes
I have not = I havent
He has not = he hasnt
ever, never, since, just, already, lately, yet, not yet, this year, this week, so for.
