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

I read somewhere that Newton wanted there to be seven colours because that’s a lucky number. Of course rainbows are a full spectrum so have as many colours/shades as you want