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Blue Water

  1. Mar 3, 2006 #1
    blue Water !!!!!!!!!!

    i have been told that water is a clear liquid ignooring any impurities, and that the ocean is blue because of the sky. This i am perfectly willing to accept, however if you fill a white bucket full of ordinary water from a tap in a white room with no windows, why does it appear blue?

    Thanks, Chris
  2. jcsd
  3. Mar 3, 2006 #2


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    Water absobs the other colors somewhat. Clear doesn't necessarily mean colorless. That's also why pictures taken underwater tend to get bluer as you go deeper. In some places, the tap water may also contain trace minerals that make it more blue.
  4. Mar 3, 2006 #3
    The reason water is blue isn't because the sky is blue. It's because the water enhances the scattering of the blue wavelengths. The more water i.e., deeper) the more scattering of blue. That's why shallow water appears clear, deeper water appears green, and deeper water appears blue. Eventually, the visible wavelengths no longer penetrate, and the deepest water is absent of visible light.
  5. Mar 3, 2006 #4


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    I have visited http://www.nps.gov/crla/" [Broken] many times, it is blue whether the sky is cloudy or clear.
    Last edited by a moderator: May 2, 2017
  6. Mar 3, 2006 #5
    Thanks alot, i understand now :D
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