RAINBOW COLOURS SPECTRUM

Spectrum is a nice English word. It simply means a "sequence" or "series". However, in science it means a "sequence of colours". After rain, sometimes a spectrum of colours appears in the sky. Rainbow is another nice English word for the spectrum of colours of sunlight.

Sunlight usually appears as white in colour but white colour is actually a spectrum of seven colours: violet, indigo, blue, green, yellow, orange, red.

It is interesting to note that there are also seven letters, in the word "rainbow" : r. a. i. n. b. o. w. After rain when rays of sunlight are reflected, refracted and dispersed by raindrops, a rainbow appears in the sky.

 

Reflection of light is coming back of light-rays from the surfaces of raindrops. Some rays of light are transmitted through the surfaces of raindrops, for which the word "refraction" is used in the language of science. Dispersion is the division of sunlight into rainbow colours. The combining effect of reflection, refraction and dispersion of sunlight after a rainfall is seen as a rainbow of seven colours by a human eye. In science laboratories, prism experiments are common for dispersing sunlight in the colours of a spectrum.

Sometimes rainbow colours are seen in falling waters of waterfalls. In some water fountains such colours are also seen. Similarly rainbow colours are reflected in the soap-bubbles. Flying soap-bubbles usually get kids' attention. A child can see all rainbow colours in a single soap-bubble only by blowing a small pipe made of plastic, clay or any other such material.

By: Ashraf Naushahi

(Educator, Writer, Book-Reviewer, Specialist in English Literature, Translator)