Question

(a) Name any two phenomena of light which cause the formation of a rainbow.
(b) A particular colour in the rainbow makes an angle of ${42.7^ \circ }$ with the line of vision. What is the colour?
(c) What will bet the shape of a rainbow when viewed from:
i. Terrace of a house?
ii. Aircraft flying very high.

Answer 1

Hint:The sunlight enters the water drops in the atmosphere, it refracts into it and then it undergo the reflections inside the surface of droplets and then comes out as the spectrum of the seven colours as violet, indigo, blue, green, yellow, orange and red.

Complete step by step solution:
The light is the electromagnetic waves that are visible to the human eye. They move from one place to the other as the waves and it possesses the particle nature and the wave nature in it. This behavior is called wave particle duality of the light.

(a) The rainbow is formed by the process of refraction, total internal reflection and the dispersion of the light in the droplets of the water that causes the spectrum of the light in the sky. This results in the rainbow.

(b) Red is the only colour that deviates the most from the main path of the light than the other colour by making the angle of ${42.7^ \circ }$ with that of the line of vision.

(c) i. When the rainbow in the sky is viewed from the building terrace, it appears as a large arc on the sky.
-But when the rainbow is viewed at the top from the flying aircrafts very high, it appears as a full circle of the spectrum of the light.

Note:The rainbow is always formed opposite to the direction of the sun and it mainly occurs when both the raindrops and the sunlight comes in the atmosphere at the same time. The light that disperse in the droplets appears as a spectrum of the seven colours.