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Homework Help: A point charge near a stream of water

  1. Jul 16, 2010 #1
    1. The problem statement, all variables and given/known data
    if a point charge is brought near a narrow stream of water will the water be attracted to the charge, repelled from it, or neither? why? water molecules are permanent electric dipoles.


    2. Relevant equations
    not sure


    3. The attempt at a solution
    i dont think the water would be affected by the charge
     
  2. jcsd
  3. Jul 16, 2010 #2
    This comes up a lot.

    A uniform electric field will torque but not pull or push a dipole. But a point charge doesn't have a uniform field, right?

    Q: what are the forces on a dielectric body in an electric field? The answer has to do with the Maxwell stress tensor. Hint: there are US patents for fluidic pumps with no moving parts that are based on these principles.
     
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