how is indigo a color in the rainbow?

Question

Growing up, I was taught that rainbows have 6 colors. Red, orange, yellow, green, blue, and purple. It makes sense as it goes from primary color (red) to secondary color (orange) back to primary (yellow) back to secondary (green), to primary (blue) and finally ending on secondary (purple). Indigo is a blend of blue and purple, but purple is a blend of red and blue…..

In: Physics

Answer 1

English is full of fishy lists of seven of things because seven was a Christian number and people loved there being seven continents/colors/seas etc in ways that really don’t make much sense