why is there no black in the rainbow colours?

Answer 1

In optics, black is the absence of color. In other words, if you were to subtract all colors you would be left with black. White light (such as light from our sun) is all of the colors combined with blue, red and green being the primary colors in optics. When the three primary colors are added together, you end up with white.

When you see a rainbow, it is because there are many tiny water droplets present. These color droplets act like prisms to separate white light into the visible spectrum of colors which includes all colors that we see. However, our eyes only pick out red, orange, yellow, green, indigo and violet.

In the absence of white light, there would only be black.

Here's an interesting reference I found about rainbows on Titan (one of Saturn's moons). This article uses illustrations to show how rainbows form and also gives a cool example of rainbows forming elsewhere than on Earth:
http://science.nasa.gov/headlines/y2005/25feb_titan2.htm

Answer 2

Pink Floyd Stole black from the rainbow.

Answer 3

The rainbow (red,orange,yellow,green,blue,indigo,violet) occurs
because light (from the sun) gets scattered by the presence of moisture in the sky. Blackness means as ABSENCE of color, or an absence of light being reflected from a surface.

Answer 4

Because rainbows are caused by the reflection of light, and black is not actually a color, it is the absence of color and light.

Answer 5

black does not exist - it is merely the absence of light.

rainbows are caused by reflected light - so by definition you can't have black.

by the way, black is not a colour (neither is white).

Answer 6

Because black is not part of the colour spectrum!

Answer 7

black does not represent the group of colours. it is the place where no light is there.

Answer 8

Black and white are not colors.

Answer 9

Black is not a color. Black is the lack of color.

Answer 10

Its not in the color spectrum of light reflection.