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Measuring surface tension / bouncing water droplets

  1. May 20, 2005 #1

    Question one: How do u measure the surface tension? (I'm looking for the experimental method now, not the theoretical one by itself)

    Question two: When ejecting water droplets at a high velocity at a small angle to a water surface/body, the droplets might not merge with the body of water, but rather bounce off it and lay a couple of seconds as droplets before merging with the body of water.


    It has got to do something with surface tension and the polarity of the molecules being directed outwards I think. The surface tension in the manner that the droplets bounce off due to the speed they hit the surface at, and polarity because they don't merge. But how exactly does this work? I'm thinking that the H-O-H turns its negative side (the O) inwards in the droplets, and the surface of the water body behaving in the same way, turning the outer molecules inwards (the O towards the body itself). The charges + and + hence appell eachother and the droplet may be able to float a while.

    The question is how this works _really_? I've heard something about charged tops or something, or is it that an airpocket is created between the droplet and the body? Please help me =)

  2. jcsd
  3. May 22, 2005 #2
  4. May 30, 2005 #3
    I really need help??!
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