Why does a rainbow has seven colours?

Question

Please don't think I am stupid as this is my homework and I am still trying to find a answer to this question.If you can answer this question please tell me the wedsite if you can.

Thanks a lot for those who can answer!

Answer 1

The sun light has these seven colours.As the rain drops act like prism and refract(bend) this sun beam,the sun light splits into seven colours.

Answer 2

A rainbow does not have just seven colors.  The colors of the rainbow occur because the rain drops act like a prism and split white light into the full visible spectrum of light.  In reality, there are an infinite number of colors of light that exist in a rainbow.  People have classified these colors broadly to fall into seven different categories, but the rainbow is really a continuous and gradual change from red to violet - there are not seven separate streaks of color.  

Check out this website: http://en.wikipedia.org/wiki/Rainbow

Answer 3

Light can pass through a spherical rain drop in two distinct paths (often causing two distinct rainbows).  A rainbow will appear in a different location for two observers separated by a significant distance (you have a very personal view).  The raindrops separate out the spectrum of photon wavelengths (as does a prism).  The human eye has three different type cones in the retinal that perceive three different primary colors (each cone fires for a range of photon wavelengths).  All other colors are a mixture of the primary colors (blue + yellow = green, etc.).  The longest wavelengths (red) are weaker than the shortest more penetrating wavelengths (violet).  There are also photons that can't be seen (infrared is below red and ultraviolet is above violet).

Answer 4

actually it reflects the visible light spectrum of solar radiation.. so it shows all color of visible light..

Answer 5

its simple man....white light is made up of seven colours that is the spectrum...vibgyor. all these colours have same speed in air so they appear to be white...when the ray of light enters any other medium(like raind drops or moisture which act as a prism), speeds, refractive indexes of all its component colours differ. therefore all colours bend at a specific angle and we are able to see all seven colours...

Answer 6

Because (white) light is made up of those 7 colours, the reason you see them separated is because the white light from the sun is refracted through the raindrops and moisture in the air.

Answer 7

This goes back to the experiment that Sir Isaac Newton did around 340 years ago ( in 1666).

He took sunlight coming through a window blind and passed it through a prism. He then viewed the spectrum that emerged and proceeded to name the colours. He identified the 7 colours that we are all familiar with. He then reversed the process through a second prism and saw white light again so proving that the white light had been split up as it passed through the first prism. The light splits up because each wavelength refracts ( bends ) by a slightly different angle and so it separates out into the constituent colours (wavelengths) .

Answer 8

As far as  know rainbows contain lots and lots of colours. Only the prime 7 can be seen easily with our eyes.

Answer 9

there are 7 different colors of light in whight light along with other light you can't see that are all refracted different amounts due to their wave length and frequency by drops of rain.

Answer 10

it's actually every color... even invisable colors. they just decided to only put 7 names in it to make it easier to remember. but there's also infared and ultraviolet also

Answer 11

The number of colours in the rainbow depends on where you draw the lines. Actually, the colours are literally a continuous spectrum between red and violet, and there isn't really any widely-recognised distinction between violet and indigo.

The reason we think of seven colours is that Sir Isaac Newton, who carried out the first scientific investigation into light and colour, was a highly superstitious man. He wanted there to be seven colours, because he regarded seven as a numerologically significant number - and because it matched the number of musical notes and days of the week. He therefore split the extreme end of the spectrum into violet and indigo, creating the seven colours we recognise today.

Answer 12

Rainbows appear as the sun is shining in one part of the sky and rain drizzling in the opposite part, and if you turn your back at the direction of sun rays, a spectrum of colour appears like a bow, and if we look at the rainbow from a high enough building or from a low flying aircraft, the bow is actually a circle, that's because thousands of tiny spherical drops of H2O acts like prisms.

Ray of sunlight enters the tiny sphere of H2O near its top surface, dispersed and reflected into the water-sphere according to their frequencies, violet being deviated the most and red the least, and on reaching the opposite side of the water-sphere (convex and concave), colours of light partly refracted out into the air and partly reflected back into the lower surface of the sphere, this cycle of refraction and dispersion continues.

The angle of red light disperse at 42o and the angle of violet light disperse at 40o, drops of water-sphere when look from another angle forms other peoples rainbow in bow shape because the ground's in the way.

A double rainbow results from double reflection (and extra refraction loss), thus the secondary bow is much dimmer.