Rainbows Jun. 2013 | Page 3

Colours

What makes the colours in a rainbow?

The traditional description of the rainbow is that it is made up of seven colors - red, orange, yellow, green, blue, indigo, and violet. Actually, the rainbow is a whole continuum of colors from red to violet and even beyond the colors that the eye can see.

The colors of the rainbow arise from two basic facts:

-Sunlight is made up of the whole range of colors that the eye can detect. The range of sunlight colors, when combined, looks white to the eye. This property of sunlight was first demonstrated by Sir Isaac Newton in 1666.

-Light of different colors is refracted by different amounts when it passes from one medium (air, for example) into another (water or glass, for example).

20/06/2013

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