prism

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Rafe
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prism

Unread post by Rafe » Mon Nov 12, 2012 2:17 pm

why the composite color of sun rays like orange isn't divided through prism

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Phlembac Adib Hasan
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Re: prism

Unread post by Phlembac Adib Hasan » Mon Nov 12, 2012 4:36 pm

I am not clear enough to answer. Please do me a favor, explain a bit more.
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Rafe
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Re: prism

Unread post by Rafe » Tue Nov 13, 2012 5:06 pm

We know that the 7 colors of white light are divided through a prism because in prism they go in different velocity.but there are 4 composite colors in that 7 colors.so why shouldn't they divided

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Phlembac Adib Hasan
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Re: prism

Unread post by Phlembac Adib Hasan » Tue Nov 13, 2012 7:17 pm

Rafe wrote:We know that the 7 colors of white light are divided through a prism because in prism they go in different velocity.but there are 4 composite colors in that 7 colors.so why shouldn't they divided
Wave-length of light is very important here. Dispersion is a continuous process. The shorter the wave-length, the greater the deviation. After passing through prism, different lights spread according to their wave-lengths. But because of continuity, as soon as wave length decreases, the color tends to green and we see something like a shade of red, getting yellower. It is because green is getting dominant over red. That's why orange and other composite colors are seen. But if you pass only orange or only yellow color through prism, it must disperse.
Last edited by Phlembac Adib Hasan on Wed Nov 14, 2012 9:14 am, edited 1 time in total.
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sowmitra
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Re: prism

Unread post by sowmitra » Wed Nov 14, 2012 12:00 am

Phlembac Adib Hasan wrote:Web-length of light is very important here. Dispersion is a continuous process. The shorter the web-length, the greater the deviation. After passing through prism, different lights spread according to their web-lengths. But because of continuity, when web length decreases the color tends to green and we see something like a shade of red, getting yellower. It is because green is getting dominant over red. That's why orange and other composite colors are seen. But if you pass only orange or only yellow color through prism, it must disperse.
@Adib: Adib, it will be "wavelength", not web-length. ;) I don't think it's a willing mistake but please be careful from next time. :|
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Phlembac Adib Hasan
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Re: prism

Unread post by Phlembac Adib Hasan » Wed Nov 14, 2012 9:12 am

ভাই গো, এইটা আমার দোষ না। প্রোগ্রামিং শিখে আর সবসময় নেটে বসে থেকে আমার এই দশা হইসে। যেমন এখন আমি অন্যমনস্ক অবস্থায় আর colour লিখতে পারি না color লিখে ফেলি; background-color লিখতে লিখতে এটা হইসে। একইরকমভাবে এখন আমি খেয়াল না করে লিখলে web-ই লিখব, wave না। :cry: সবই কপালের দোষ। যাই হোক উপরেরটা এডিট করে দিলাম।
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sowmitra
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Re: prism

Unread post by sowmitra » Wed Nov 14, 2012 4:21 pm

ভাই, সমস্যা নাই। :) তাই তো বলি, আদীবের তো এই ভুল হওয়ার কথা না। :roll: যাই হোক, নেট থেকে একটু রেস্ট নাও। পড়ালেখার কী অবস্থা ? মনে হয়, ফাইনাল পরীক্ষা আসন্ন............... :geek:
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Re: prism

Unread post by SMMamun » Thu Nov 15, 2012 8:47 pm

Nicely explained by Adib! Just a few points added:

The prism in fact divides the white color of sun ray into “infinitely many” colors (frequencies)—into lights of the entire Visible Spectrum. The so-called 7 colors are just seven colors dominantly perceived/felt by the eye and do not tell the whole/true story. :)

Now among those infinitely many colors, exactly how many can be uniquely/separately perceived by a human eye may vary from person to person and depend on the environment/surrounding in which the colors are observed. It is even possible for a human eye to differentiate between colors separated by 1 nanometer of wavelengths.

You and I may have just one or two reds, but the poets have many different reds. Girls may have more colors than boys do. Well, even if I might be joking here, the key thing is that color is a mental perception, has something to do with the anatomy and physiology of eyes, and varies from animal species to species. Not all the blues are the same blue, not all the greens are the same green. :)

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