Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

I Clouds don't refract light?

  1. Apr 3, 2016 #1
    Hi all.

    I have just passed my phisics 2 exam since a little time, and during the study of refraction a questions arose into my head: Why clouds does not refract light?
    They are water vapour after all, so why do they not refract light, like it happens after raining with rainbows?
     
  2. jcsd
  3. Apr 3, 2016 #2

    blue_leaf77

    User Avatar
    Science Advisor
    Homework Helper

    Atmosphere does refract light.
     
  4. Apr 3, 2016 #3
    I never saw any cloud refracts the different colors of the light though, except some halos around the moon at night.
     
  5. Apr 3, 2016 #4

    davenn

    User Avatar
    Science Advisor
    Gold Member

    and of the sun, also look at
    https://en.wikipedia.org/wiki/Noctilucent_cloud
    and this ( I have seen many times)

    th.jpg

    all caused by the refraction of sunlight through ice crystals in clouds


    Dave
     
  6. Apr 3, 2016 #5

    blue_leaf77

    User Avatar
    Science Advisor
    Homework Helper

    From your wording, it sounds like your picture of refraction is a light being dispersed into different colors. That is dispersion, not refraction. Clouds can also cause dispersion though, the example of which has been given by davenn above, as well as the halos.
     
  7. Apr 4, 2016 #6

    davenn

    User Avatar
    Science Advisor
    Gold Member

    dispersion may better describe it
    I, maybe mistakenly, had always thought of it as refraction through the ice crystals
    Refraction resulting in dispersion ?? :-p

    Dave
     
  8. Apr 4, 2016 #7
    Both refraction and dispersion are occurring. Dispersion occurs because of wavelength-dependent refraction.
     
  9. Apr 4, 2016 #8
    So all clouds refract light and clouds with ice crystals disperse it due to the crystal structures interacting with the light at various wavelengths/frequencies?
     
  10. Apr 4, 2016 #9

    ProfuselyQuarky

    User Avatar
    Gold Member
    2016 Award

  11. Apr 4, 2016 #10
    Any time light passes through a medium it will refract, ie, the vacuum/atmosphere interface, the atmosphere/water interface, etc.The velocity of light is different in air vs, a vacuum, vs water. The magnitude will depend on the medium's refractive index. As someone else said, the dispersion is wavelength dependent.
     
  12. Apr 4, 2016 #11
    We get that effect here a lot in sunny S Florida, especially with our summertime clouds.
     
  13. Apr 4, 2016 #12

    ProfuselyQuarky

    User Avatar
    Gold Member
    2016 Award

    I live in sunny S California, and we have summertime clouds, too :wink:
     
  14. Apr 4, 2016 #13
    Then look up more often Quarky! :-p
     
  15. Apr 4, 2016 #14

    ProfuselyQuarky

    User Avatar
    Gold Member
    2016 Award

    Will do! I tend to walk looking slightly down, in fear of tripping on something, but then I’m unaware of what’s on top of me . . . or in front of me (like that lady holding a baby at the grocery store or that metal pole at the tennis court) :rolleyes:

    I have to pick between cracks, poles, ladies, and refraction of light. Which one is most important?? :smile::smile:
     
  16. Apr 4, 2016 #15
    The main effect in clouds is the scattering of light (Mie scattering). Water droplets in the clouds scatter all wavelengths from the sun, making the clouds appear white. In the sky, the molecules are small, Rayleight scattering predominates and is strongest for blue wavelengths.
     
  17. Apr 4, 2016 #16

    Andy Resnick

    User Avatar
    Science Advisor
    Education Advisor
    2016 Award

    As pixel mentioned, clouds (whether composed of ice or liquid water) primarily scatter light, clouds appear white because the light is multiply scattered. Like snow. And milk.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Clouds don't refract light?
  1. Refraction of light (Replies: 10)

  2. Refraction of light (Replies: 1)

  3. Refraction of light (Replies: 33)

  4. Refraction of light (Replies: 19)

  5. Refraction of Light (Replies: 2)

Loading...