The document discusses the phenomenon of dispersion of white light and the visible light spectrum. It explains that when white light passes through a transparent medium, it splits into its constituent colors from red to violet due to dispersion. The range of the visible light spectrum is from 0.4 to 0.7 microns. It also defines primary colors as red, blue and green which when mixed together produce white light, and secondary colors as cyan, magenta and yellow which are obtained by mixing two primary colors. Complementary colors are pairs of primary and secondary colors that combine to make white light.
1. PANCHAYAT UNION MIDDLE SCHOOL, VISWANATHAM
SIVAKASI UNION,
VIRUDHUNAGAR DISTRICT,
TAMILNADU STATE, INDIA-626124.
CELL NO 97510-45246. Exit
2. Dispersion
Dispersion of White light
Colours
Colour Filters Home
Mixing Colour or Spectral Colours
Colour Blindness – An Activity
Mixing of Colours – An Activity
Newtons’ Colour Disc PHYSICS
3. The phenomenon by which a ray of light splits into its
constituent colours when 00is passed through a
it
transparent medium is known as dispersion.
Red
Orange Range of
Yellow Visible
Green Spectrum
Blue 0.4 microns to
Indigo
0.7 microns
Violet
Spectrum is the band of colours obtained due to
the dispersion of Light. Rainbow
6. Pigment is an optically active substance which may be synthetic or of
Mineral animal or vegetable origin.
7. Pigment is sensation produced in the brain due to the excitation of retina, by
Colour is a an optically active substance which may be synthetic or of
Mineral animal or vegetable origin.
electromagnetic waves.
The range of wavelength of these waves is 4000Å to 8000Å
Angstrom (Å) : It is the unit used to measure wavelength of electromagnetic
radiation. 1 Å =10-10 m =10-8 cm
8. Red
Orange
Yellow
Green
Blue
Indigo
Violet
Primary Colours
Red Blue Green
9. The Primary colours are the
white light.
Colours which when mixed
in equal proportions
give white light.
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10. The colours obtained by the mixing two primary colours are called
Secondary Colors
Secondary Colours
Cyan Magenta Yellow
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Red + Green = Yellow
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Yellow
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12. Red + Blue = Magenta Magenta
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13. Pro
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Green + Blue = Cyan
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Cyan
14. The Secondary colours are obtained by projecting light of one colour on the other
and the rocess is known as colour mixing by addition. The colurs thus obtained are
called additive colours
Cyan Magenta
Yellow
15. Complementary Colours can be defined as pair of colours one primary and other
secondary colour, which on mixing forms white light.
Secondary Colours are known as subtractive primaries as they are obtained by
subtracting one of the primary colours from white light.
White
White White
16. Yellow + Green = White White
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17. Pro
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Green + Cyan = White
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White
Pr oje
18. Pro
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Red + Cyan = White
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White
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19. Colour Triangle
Primary Colours Secondary Colours
Red Magenta
Green Yellow
Blue Cyan
Cyan
The order of the colours is such that the sum of any two primary colours at the
Corners gives the secondary colors between them.
The sum of the primary colour on the vertex and the secondary colour on the side
opposite to the vertex produces white light.
20.
21.
22. The Rod shaped cells are sensitive to brightness of light. The Cone shaped cells
orRetina : The retina, the colours.of the human eye, Consists ofsensitive andnumber
cones are sensitive to screen There are red sensitive, blue a very large
green sensitive cones. Colourare rod shaped cells and cone shaped cells.cones
of light sensitive cells. They blind people have less number of particular
than people with normal vision. Hence they get colour confused.
Retina Rod shaped Cells
Cone shaped Cells
23. If you see the No 12. your vision is normal else not.
24. Look at this picture and click on the number you see.
a) 21 b) 24 c ) 74 d) No number