Question

In a primary rainbow what is the order of colours observed from earth?
A. Violet innermost, Red outermost
B. Red innermost, Violet outermost
C. Random
D. White and dark alternatively

Answer 1

The above problem can be resolved using the fundamentals for the formation of rainbows. The rainbow is seen in the form of a band of seven colours popularly known as VIBGYOR. These seven colours result from the dispersion, which occurs due to water droplets' interaction and the radiation of white light from the sun.

Complete step by step solution:
The rainbows are formed by the dispersion of white light coming from the sun. And this dispersion brings out the splitting of white colour into the band of seven colours known as the rainbow. The seven colours are collectively known as VIBGYOR, such that each word has its meaning.
The letters mean as,
V - Violet
I - Indigo
B - Blue
G - Green
Y - Yellow
O - Orange
R - Red
In the above series of colours, the violet appears to be at the innermost part of the band, and red occurs on the outermost part of the, and the observation is made only when observed from the earth's surface.

Therefore, the order of colours observed from earth is such that violet is at Violet innermost and Red is at the outermost and option (A) is correct.

Note: Try to understand the concept behind the formation of the rainbow by the phenomena of dispersion. The dispersion is the phenomenon by which the white light gets divided into the seven colours of different wavelengths. These seven colors form a band, which is collectively known as the rainbow. The rainbows are formed after the rain showers in most cases.