Page 2 - Lesson note recombination of white light
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A spectrum of seven colours of lights can be recombined to form back white light.
This can be done by placing two glass prisms side by side. But, place the second
glass prism in an inverted position. When white light passes through first prism it
disperses the light into seven colours and when this beam of light enters the second
prism which is placed in an inverted position, a white light is obtained when it comes
out of the second prism.
The seven coloured lights recombine to form white light due to second glass prism
which is placed in a reversed position.
The rainbow
Rainbow is formed when it is raining at the time of sunshine. When the white sunlight
falls on the raindrops and leaves them, then the white light is refracted and an arc of
seven colours is formed in the sky. In this situation, tiny raindrops act as glass prism
splitting the white sunlight.
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