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 ${42.7}^o$ with the line of vision. What is the colour?
(c) What will be the shape of a rainbow when viewed from:
i. Terrace of a house?
ii. Aircraft flying very high.

Answer 1

(a) Refraction and total internal reflection are the two phenomena which causes the formation of rainbow. Just like when light passes through a prism, due to refraction of light, all the seven colors of white light can be seen on the creen.
(b) Red : As red color deviates the most least from the main path and makes an angle of ${42.7}^0$ with the line of vision.
(c) i. When we see a rainbow from the terrace of a building, it will be looking like an arc.
ii. Aircraft: When we see a rainbow from a flying aircraft, it looks like a circle.