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Electric field in water, using voltage, without electrolysis

  1. Oct 6, 2015 #1
    Hi!

    Can we create electric field in water, using electrodes (say 10-15V of voltage difference), without having electrolysis or arc in water? (the water can be salty). I just read that insulated electrodes can be used. but I'm not sure.

    PS: Sorry if the question sounds silly. My field of study is so far from these topics :)

    Thank you :)
     
  2. jcsd
  3. Oct 6, 2015 #2

    jtbell

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    Staff: Mentor

    Yes. In an introductory laboratory course, many years ago, I used an electric field mapping apparatus which consisted of a shallow tray of water with electrodes of various shapes. I don't remember what the voltage was. As I recall, we did have some small bubbles forming at the electrodes, but they didn't cause any problems.
     
  4. Oct 6, 2015 #3
    @jtbell Thank you for your reply. Actually those small bubbles matter. I'd like to know if there is a way to have the field without having the bubbles (which are the result of electrolysis).
     
  5. Oct 6, 2015 #4
    Any suggestion? :)
     
  6. Oct 7, 2015 #5

    Svein

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    Science Advisor

    Some colleagues of mine did extensive measurements on oil pipes under water, and they concluded that the voltage had to be very low. I think it was on the order of 0.2V.

    Of course, this was in the North Sea. Very salty water.
     
  7. Oct 7, 2015 #6
    Electrolysis does not occur if the voltage is less than 1.7 V.. Above that as long as there is some current flowing you will get electrolysis.
     
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