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Can anyone tell me why clouds float and dont fall down?

  1. May 30, 2004 #1
    Can anyone tell me why clouds float and dont fall down ? tx
  2. jcsd
  3. May 30, 2004 #2

    Doc Al

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    Staff: Mentor

    Because the droplets of water are so small their terminal velocity is essentially zero. They are easily supported by rising air. When the droplets get too big, they do fall--as rain.
    Last edited: May 30, 2004
  4. May 30, 2004 #3


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    There is/was a website associated with Scientific American which invited people to ask questions to the experts. Years ago I sent a question to them, but it never appeared at the website and I never got a reply. Maybe somebody here knows the answer.

    When a storm moves west-to-east across a continent, does a typical molecule in the air over the west coast get pushed all the way to the east coast, or does it merely move east for minutes or hours, whereupon it gets left behind the storm front?
  5. May 30, 2004 #4
    I thought most of the moisture present in clouds was in the form of ice crystals of various geometric shapes. This would present a much larger surface area to mass ratio over spherical droplets, making them even easier to support.

    But this isn't my field, and I might be completely wrong (or just saying the same thing in different terms) or there might be so amny different conditions in different kinds of clouds.
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