light -colour exercises

When white light shines into a spherical water drop it is refracted slightly. The light then bounces off the inside of the opposite wall of the water drop by total internal reflection. The light then undergoes a second refraction as it leaves the water droplet. The double refraction of light splits it into its component colours. The higher the sun is in the sky the greater the angle at which it enters the water droplet. The light will be refracted closer to the bottom of the sphere causing the internally reflected light to emerge at a more shallow angle. So the rainbow will appear to be lower in the sky.

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Colour exercises
1) Why must the sun be behind you when you look at the rainbow? Use the term "*Total internal reflection"* in your explanation 2) As the sun rises in the sky will a rainbow get higher, lower or stay the same with reference to its position inthe sky? Solution.