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Creating static electricity from an electrical current

  1. Dec 28, 2012 #1
    Is it possible to use an electrical current (from mains electricity) to create static electricity on a conductive surface (that is not earthed) without the two coming into direct contact? See attached image.

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  2. jcsd
  3. Dec 28, 2012 #2


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    bgchfcrzyft, Welcome to Physics Forums!

    I think static electricity would not be created. Electrical mains are Alternating Current (AC) which means they change polarity every half cycle. So even if during one half cycle a nearby conductive surface got charged up it would be discharged by the next half cycle.

    If your goal is to create static electricity (static charge) you can always search using "Google" for example. You'll find Van de Graff generators plus many more machines that generate static charge. I especially like the Kelvin Water Dropper.

  4. Dec 28, 2012 #3
    Just as a modulating electric field creates a magnetic field, a modulating magnetic field will create an electric field.
  5. Dec 29, 2012 #4
    The alternating voltage in the wire will induce an alternating voltage in the surface. If the surface is big and very close to the wire you can get a shock from it. e.g you take an insulated wire carrying mains electricity and wrap a big piece of aluminum foil around it, the foil will have no contact with the wire but the capacity between wire and foil is relatively large so you could get shocked when touching the foil.
  6. Dec 29, 2012 #5
    Thanks to everyone for their quick responses.

    Bobbywhy - could you change the AC to DC with a transformer and make it work?

    Judgeking - are you suggesting that if you created an electromagnet the magnetic field could create static on the adjacent surface?

    DrZoidberg - I will give that a try, cheers.
  7. Dec 29, 2012 #6
    Bobbywhy - could you change the AC to DC with a transformer and make it work?

    A transformer does not change AC to DC.

    Judgeking - are you suggesting that if you created an electromagnet the magnetic field could create static on the adjacent surface?

    The wire in your diagram IS an electromagnet.
  8. Dec 29, 2012 #7
    Try what? Shocking yourself with mains ac?
  9. Dec 29, 2012 #8


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    You have demonstrated a clear lack of understanding of basic electricity.
    The easiest way to change that is to learn to use the terms correctly and how the most basic processes function. You will build your entire understanding of nature based on this foundation. So, I recommend that you read and study these Wiki summaries:

    “A transformer is an electrical device that transfers energy by inductive coupling between two or more of its windings. A varying current in the primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic flux through the secondary winding. This varying magnetic flux induces a varying electromotive force (EMF), or "voltage", in the secondary winding. This effect is called inductive coupling.”

    “In electrical engineering, two conductors are referred to as mutual-inductively coupled or magnetically coupled when they are configured such that change in current flow through one wire induces a voltage across the ends of the other wire through electromagnetic induction.”

    “A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction. The process is known as rectification.”

    Here are two important statements taken from the Wiki page about static electricity:
    “Static electricity is named in contrast with current electricity, which flows through wires or other conductors and transmits energy.”
    “The phenomenon of static electricity requires a separation of positive and negative charges.”

    After you’ve done your “homework” on these basics, if you still have some questions or doubts, return here to Physics Forums and post them. Members here are always ready and willing to assist any true searcher willing to learn science.

  10. Dec 30, 2012 #9
  11. Jan 7, 2013 #10
    Thanks everybody for your help, much appreciated.

    As you have already guessed I am a complete novice when it comes to electricity and anything more than basic physics; it's been over 20 years since I studied my highers at school so I am a little out of practice but have started looking into a few ideas to rekindle an old fascination with physics with a friend who knows only a little more than I do.

    I shall go away and do my 'homework'' and will return, maybe with a few more questions.


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