Now suppose the raindrop that we have been discussing is directly in front of you and at an angle of 42 degrees up: the angle of red light. See Figure 3.

Figure 3.  Red light emerging from the single raindrop of the previous example. Sketch from About Rainbows.

Then the red light from that drop hits your eye and you see red. The violet light from that drop, however, is higher (at 40 degrees) and misses your eye. Maybe it hits your hat and you don't see violet. How, then, do you see all the colors in the rainbow? And how do you see the whole bow and not just a single light?

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