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Creating static charge with a voltage source

  1. Mar 20, 2010 #1
    I'm learning about static electricity. All the examples always bring up the experiments with rubbing a balloon with your hair and combinations like that.

    I've found a page that lists what kind of charges certain materials tend to have.

    http://www.school-for-champions.com/science/static_materials.htm

    So now i'm wondering, is it possible to attach a negative electrode of a 12V source to a piece of glass and expect that it will get positively charged?

    Could i also connect myself to the negative electrode and expect that I will also be positively charged?

    Both myself and the glass will be standing on a insulator.

    I'm going to try that, and post the results.
     
  2. jcsd
  3. Mar 20, 2010 #2
    Well, that didn't work very well :)

    So I tried something else. I took a piece of aluminum foil and connected it to the + side, and than after about 30 seconds, i disconnected it. I thought that now when i bring the positive electrode to the aluminum it would move a bit, but it didn't.

    My assumption is that either the voltage or the capacitance of the foil is to small, to accumulate enough charge for the force to be noticeable.

    So how do I increase the capacitance of the foil? Bi making it's surface larger?

    I think the formula for the capacity of a capacitor can't apply here.

    [tex]C = \epsilon_0 \epsilon_r \frac {S}{d}[/tex]

    What is the dielectric here? The piece of plastic he foil was placed on, or the air around it :) ?

    And what would d represent?
     
  4. Mar 20, 2010 #3

    Dale

    Staff: Mentor

    A typical static electric charge can be 10s or 100s of kV. A 12 V static charge is negligible.
     
  5. Mar 22, 2010 #4
    Ok, so that's a fail than.

    What about the capacity?

    If I had a full metal cube which i attach to a positive electrode, how can I calculate the amount of excessive charge? Considering that the cube is placed on an isolated material and the electrode is removed.
     
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