How a Rainbow is Formed

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A 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 difference causes light to diverge in different angles as it comes out of the prism. This splits the white color into many components, which are different colors. Since a raindrop contains two refractive indexes, it produces the different colors 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 always depend on the refractive index of both media. Now, the refractive index keeps on changing depending on the wavelength of the light passing through. Light, as we know, it is a wave that has different wavelength. Each wavelength represents a different color. Thus, different colors 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 see a 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 the little droplets that act a prism. The rays will get refracted twice, thus, producing different variety of colors. However, each drop will only produce one color thus ... ... middle of paper ... ...is generally known as Rayleigh scattering. The blue color, which is observed in the sky, is due to the Rayleigh scattering. As light travels in the atmosphere, it comes across gas molecules which absorb most of the colors with shorter wavelength. Colors such as red, orange, yellow are least absorbed. Blue, being a color with short wavelength, gets absorbed in the molecule. It is then radiated into all directions. Now, this is the color that reaches our eyes because it gets scattered in all directions, hence a blue sky. Still at times, the sky will have a pale blue color. This is because the scattered blue colors have to go through other gas molecules, and in turn get scattered more. It is like dividing a particular mass into many pieces, and the final results will be just tiny masses. This is how blue color gets divided before it reaches our eyes.

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