and why is it those seven colours?
2007-02-24 11:38:54 · 4 answers · asked by Imagica 2 in Science & Mathematics ➔ Weather
A rainbow is made up of all the colours that our eyes can see.
There are seven of them; red, orange, yellow, green, blue, indigo and violet. Of course there are thousands of shades of each colour, but they are all a combination of these seven.
Light is part of what is called the 'electromagnetic spectrum'.
This contains energy which travels in 'waves' These waves can be miles apart, or millionths of an inch long. That is what they call a 'wavelength'. We may not see them all, but we sure use them all in different ways.
The biggest are radio waves, and the shortest are 'gamma waves'. In between those you will find light, t.v., ultraviolet, (the ones that can harm us if we allow them to reach our skin for too long) and x rays. There are lots more, but that's not important here.
The only waves our eyes can see are those in a tiny part of the spectrum, and that's what we call visible light.
The colours you see in anything are a result of the surface the light is shining on reflecting or absorbing the colours. Which ever colour you see is the wavelength which isn't being absorbed by it.
Black absorbs all of them, which is why it feels hotter if you wear it on a sunny day. White reflects them all, which is why it feels cooler.
When it comes to a rainbow, the water droplets in the air bend the light rays at different angles, so that each colour you see is being bent (refracted) slightly differently from the other ones, which changes their wavelenth a tiny bit.
Rainbows are a beautiful way of learning a little science!
2007-02-24 12:30:53 · answer #1 · answered by kathjarq 3 · 1⤊ 0⤋
It's how water in the atmosphere cuts white light. The moisture in the air acts like a prism forming the colors you see
AS far as the colors forming, it's the primary colors....red blue and yellow that show the most. The others are combinations of those colors....namely purple and orange.
The rainbow only has 5 detectable colors....any with seven that you've seen are probably drawings
2007-02-24 11:50:31 · answer #2 · answered by phillyvic 4 · 0⤊ 0⤋
There are many more than seven colors to a rainbow. It is an old and out of date expression to say the 'seven colors of the rainbow' as the human eye can discern at least a thousand different shades of color each one distinct. Seven is an easy number to remember and let us not forget about the pot of gold at the end of it! If you believe that then you may find yourself investing in virtual realestate as well.
2007-02-24 11:49:36 · answer #3 · answered by Tom M 2 · 0⤊ 1⤋
because it's pritty. :]
2007-02-24 11:51:59 · answer #4 · answered by [[Abby]] 2 · 0⤊ 0⤋