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Dispersion of Light. Primary Concept of Colours of Objects . When the light is incident on the object, the absorption of some colours and reflection of some colours from the object takes place. . The colour of light which is reflected from the object determines the colour of an object. .
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Dispersion of Light Primary Concept of Colours of Objects When the light is incident on the object, the absorption of some colours and reflection of some colours from the object takes place. The colour of light which is reflected from the object determines the colour of an object.
Primary Concept of Colours of Objects Dispersion of Light • When the object appears black coloured, there will be • no reflection of any constituent colour of light. • When all the constituent colours are reflected from the object, it appears white.
Dispersion of Light Primary Colours of Light and their Superposition The splitting of light into its component colours is dispersion. After the recombination of these colours white light is again obtained.
Dispersion of Light Primary Colours of Light and their Superposition When equal amounts of Red Green and Blue light are combined, they produce white light. Red, green and blue are the "primary" coloursof white light.
Dispersion of Light Primary Colours of Light and their Superposition The method of producing a wide range of colours by the appropriate mixture of these primary colours is known as an additive mixture method. The colours obtained by the mixture of primary colours are known as composite colours. Composite colours are: Yellow, Cyan and Magenta
Dispersion of Light Primary Colours of Light and their Superposition Superposition of Primary and Composite colours Any two colours, which on mixing, produces a light or white colour are called complementary colours.
Dispersion of Light Primary Colours of Light and their Superposition Colours and Pigments Pigment is a material that changes the color of reflected or transmitted light. Cyan magenta and yellow are the primary pigments. When the white light is incident on blue pigment , violet and green colours are reflected and the remaining colours are absorbed.
Dispersion of Light Mirage Mirage occurs due to total internal reflection of light. When the sun is high in the sky, the sand gets heated first and then the layers of air above it. The rays from the trees travel from an optically denser air layer to a rarer layer and bend away from the normal. This bending continues and a stage is reached where the angle of incidence becomes greater than the critical angle and total internal reflection takes place.
Dispersion of Light Mirage The totally reflected rays that reach the eyes appear to come from a point on the ground where the image of the tree is formed. Thus one sees an inverted image of the tree though there is no water around.