Rainbow

The spectacle of rainbow is one of the most amazing things that can be seen in the
sky. However, many people do not know how rainbows are formed. For a start, I will start
by explaining how rainbows are formed. A rainbow occurs as a result of refraction and
dispersion of white light, as it passes through a prism. Since a prism has two indexes,
their diference causes light to diverge in different angles as it comes out of the prism.
This splits the white colour into many components, which are different colors. Since a
raindrop contains two refractive indexes, it produces the different colours when hit by
Sunrays. These colors are what we see as a rainbow.
Now in order to understand how lights is able to be refracted in different angles, it
is important to understand the Snell's Law which states that, the refractive angle alwayss
depend on the refractive index of both media. Now, the refractive index keeps on
changing depending on the wave-length of the light passing through. Light, as we know, it
is a wave that has different wave-length. Each wave-length represents a different colour.
Thus, different colours will have different refractive index when passed through the same
media. It is important to note that light is normally refracted twice when it travels through a
prism, first on its way in, and when it is going back.
So how do we get to seea rainbow in the sky? First condition that must be fulfilled
is that the sun must be shining, more to that, the sun must be behind you and raindrops
must be present in the sky. When these three conditions are present, then the sun will
shine to thelittle droplets that act a prism. The rays will get refracted twice, thus,
producing different variety of colors.