Jump to content

How does a prism seperate white light?

Featured Replies

White light is a mixture of all the different frequencys of light but it can be seperated by a prism.

 

What I want to know is: How does a prism seperate white light into its components?

different wavelengths get difracted by a different amount which means they'll come out at different angles. and thus seperate.

  • Author
different wavelengths get difracted by a different amount which means they'll come out at different angles. and thus seperate.

 

But why can we see only the colors of visible light? Why can't we see the waves of visible light themselves?

i'm not sure i understand the question? do you mean why doesn't a beam of light seem to ripple like the surface of water?

  • Author
i'm not sure i understand the question? do you mean why doesn't a beam of light seem to ripple like the surface of water?

 

No. What I meant is that we can only see the COLORS of visible light. But if these colors are really made of waves of different frequencies, why can't we see the waves themselves and not just the colors?

well, 1/ they're far to small

2/ its not a wave of matter like a water wave. it doesn't reflect light so it's 'invisible'.

3/ our eyes interpret the waves as colours(obviously).

different wavelengths get difracted by a different amount which means they'll come out at different angles. and thus seperate.

 

Refracted, not diffracted.


Merged post follows:

Consecutive posts merged
But why do our eyes interpret the waves as colours?

 

I'm not sure, but this isn't a physics question.

  • Author
well, 1/ they're far to small

 

So if we got down to 380 to 750 nm which are the wavelengths of visible light, then could we see the waves?

What do you mean by "see the waves?" We do see the light. When light enters our eyes and hits our retinas, optic nerves are activated and carry signals to the visual cortex, which interprets it and puts together a coherent picture, etc. We have the ability to distinguish between some different wavelengths (by activating different types of nerves), which is what we call different colors. That's what color is. And, clearly, light that doesn't hit your retina isn't seen.

  • Author
What do you mean by "see the waves?" We do see the light. When light enters our eyes and hits our retinas, optic nerves are activated and carry signals to the visual cortex, which interprets it and puts together a coherent picture, etc. We have the ability to distinguish between some different wavelengths (by activating different types of nerves), which is what we call different colors. That's what color is. And, clearly, light that doesn't hit your retina isn't seen.

 

 

Still but we don't actually see the waves of visible light, we only see colors so the explanation that colors are really made of electromagnetic waves sounds fishy to me.

Edited by Uri

look, we can't see the waves directly because they are merely ocillations in the electric and magnetic fields. when you power up a van de graff generator it creates a massive distortion in the electric field yet we cannot see it. similarly for large magnets like an MRI machine.

 

they do not reflect light and so are not visible by this method. the only way we can detect a photon directly is with out eyes. photons of different wavelengths are detected by different cells in our eyes and are interpreted as colours.

 

i'm not sure what your problem with this is. perhaps if you expans on what 'seeing the waves of visible light' means.

Instead of saying

"oh, there aren't any ways to prove that light are actually real waves, so God must exist", why don't you think a bit harder and find an experimental setup to prove that light IS actually a wave ? I'll give you a clue (and a bit of self-promotion on the way) :

 

 

is a way to demonstrate that ultrasound is a wave.

As I wrote in another thread, one of man's flaw is the inability to accept life, consciousness and God for who they are and what we are and evidence really points to a God creator.

 

We are discussing physics here and only physics. Do I make myself understood?

We don't "see" light or anything else for that matter. Light that enters our retina, hits receptor cells where it causes a chemical reaction. Most people have 3 different kind of color-detecting cone cells and also rod cells, all of which are affected differently by various frequencies of light. When light causes a chemical reaction in the cells, it is amplified and converted to a nerve signal, which travels to and is interpreted by your brain as light of a certain color, intensity, and position.

 

Oh, and if you wanted to "see" light as a wave, you'd have to bounce a lot of light off the light you want to see, just as you do to "see" other objects.

  • Author
We are discussing physics here and only physics. Do I make myself understood?

 

I apologize and yes next time I will not bring God or any other topic which isn't physics (or science) related up for discussion on this board, I promise!

Archived

This topic is now archived and is closed to further replies.

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.