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Science Forum

  1. Standard member uzless
    The So Fist
    25 Feb '08 20:05
    If an object is blue because the object is absorbing all colours of the light spectrum but is reflecting the blue wavelength and white objects reflect all wavelengths consider this.

    If black objects absorb all wavelengths, and therefore do not reflect any light, how come we can see the objects? Shouldn't they be invisible?

    How do you "see" black?
  2. 25 Feb '08 20:15
    you don't see black. You see an absence of colour.
  3. 25 Feb '08 20:38
    Originally posted by uzless
    If an object is blue because the object is absorbing all colours of the light spectrum but is reflecting the blue wavelength and white objects reflect all wavelengths consider this.

    If black objects absorb all wavelengths, and therefore do not reflect any light, how come we can see the objects? Shouldn't they be invisible?

    How do you "see" black?
    You're right. We cannot see (totally) black things. That's the reason they're black.
  4. 25 Feb '08 21:17
    Originally posted by FabianFnas
    You're right. We cannot see (totally) black things. That's the reason they're black.
    So what does black really look like or is this just a theoretical thing that no-one can prove because we can't see black.
  5. Standard member ivan2908
    SelfProclaimedTitler
    25 Feb '08 21:21 / 1 edit
    "look like"


    It looks like black from humans eye perspective, snake may see that differently, carrot do not see it at all...
  6. 25 Feb '08 21:40
    Originally posted by uzless
    If an object is blue because the object is absorbing all colours of the light spectrum but is reflecting the blue wavelength and white objects reflect all wavelengths consider this.

    If black objects absorb all wavelengths, and therefore do not reflect any light, how come we can see the objects? Shouldn't they be invisible?

    How do you "see" black?
    You can't see a black hole....


  7. Standard member adam warlock
    Baby Gauss
    25 Feb '08 21:46
    Originally posted by uzless
    If an object is blue because the object is absorbing all colours of the light spectrum but is reflecting the blue wavelength and white objects reflect all wavelengths consider this.

    If black objects absorb all wavelengths, and therefore do not reflect any light, how come we can see the objects? Shouldn't they be invisible?

    How do you "see" black?
    Because of the all other colours that are being refelcted around it. But the real reason is that real black entitites don't exist. Real bodies always reflect a little bit.
  8. Standard member uzless
    The So Fist
    25 Feb '08 21:46
    Originally posted by FabianFnas
    You're right. We cannot see (totally) black things. That's the reason they're black.
    Exactly, so if someon tells you something is "green", they should really be saying that thing is "everything but green" since the object is absorbing everything except the green wavelength.

    My "blue car" should be called an "everything but blue" car.

    Or better still, a "not blue" car. My car wants nothing to do with blue.
  9. 25 Feb '08 22:21
    Originally posted by uzless
    Exactly, so if someon tells you something is "green", they should really be saying that thing is "everything but green" since the object is absorbing everything except the green wavelength.

    My "blue car" should be called an "everything but blue" car.

    Or better still, a "not blue" car. My car wants nothing to do with blue.
    Your car is a blue-rejecter.
  10. Standard member Mexico
    Quis custodiet
    25 Feb '08 22:31
    Originally posted by uzless
    If an object is blue because the object is absorbing all colours of the light spectrum but is reflecting the blue wavelength and white objects reflect all wavelengths consider this.

    If black objects absorb all wavelengths, and therefore do not reflect any light, how come we can see the objects? Shouldn't they be invisible?

    How do you "see" black?
    you can't see black because your colour blind??

    sorry couldn't resist
  11. Standard member Aiko
    Nearing 200000...!
    25 Feb '08 23:23 / 1 edit
    Originally posted by Nordlys
    Your car is a blue-rejecter.
    That should be a partly green and a partly yellow rejecter. If not mistaken.
  12. Standard member wormwood
    If Theres Hell Below
    25 Feb '08 23:49
    seeing black is not a physics question, it's a biology question. it's the way our visual cortex interprets lack of (sufficient) stimulus on photoreceptors in our eyes. and as such, it would be theoretically possible to see absolute black. it wouldn't mean that something you look at wasn't emitting anything though, just that its intensity is too low to trigger a reaction.
  13. 26 Feb '08 00:53 / 2 edits
    Originally posted by uzless
    If an object is blue because the object is absorbing all colours of the light spectrum but is reflecting the blue wavelength and white objects reflect all wavelengths consider this.

    If black objects absorb all wavelengths, and therefore do not reflect any light, how come we can see the objects? Shouldn't they be invisible?

    How do you "see" black?
    Education. You were taught to associate the concept "color black" when your eyes can't catch enough radiation in the appropriate wavelenghts to stimulate a response to your brain.


    If black objects absorb all wavelengths, and therefore do not reflect any light, how come we can see the objects? Shouldn't they be invisible?
    If the object was really black you wouldn't see it. Your definition is correct. But there are small reflections even from what we call black objects that allow you to see them.
  14. Standard member smw6869
    Granny
    27 Feb '08 03:54
    Originally posted by uzless
    If an object is blue because the object is absorbing all colours of the light spectrum but is reflecting the blue wavelength and white objects reflect all wavelengths consider this.

    If black objects absorb all wavelengths, and therefore do not reflect any light, how come we can see the objects? Shouldn't they be invisible?

    How do you "see" black?
    Good question uzless. It sure beats arguing about politics. Great site.

    F.GRANNY.
  15. Subscriber AThousandYoung
    Do ya think?
    27 Feb '08 05:08
    Originally posted by uzless
    If an object is blue because the object is absorbing all colours of the light spectrum but is reflecting the blue wavelength and white objects reflect all wavelengths consider this.

    If black objects absorb all wavelengths, and therefore do not reflect any light, how come we can see the objects? Shouldn't they be invisible?

    How do you "see" black?
    You see the contrasting colors around it.