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Static Electricity discharge question

  1. Aug 29, 2009 #1
    Why is it that someone who discharges static electricity feels a sting but the person who is receiving the static electricity doesn't feel anything?

    Thanks
     
  2. jcsd
  3. Aug 29, 2009 #2
    That's not true actually. Many times i felt the sting while the other also did. Anyhow, lets get into what really happens when this static electricity causes "stings". This is called Crown Discharge and happens when the tension between two point separated by air overpasses a certain value (relatively high) then the air becomes a conductor and so the charges move trough it. The sting felt is due to the electrons them selves as they are quite energetic and kill some cells what makes you feel the little sting.

    Any correctios are welcome :)
     
  4. Aug 30, 2009 #3
    How does the electrons gain energy? And does electrons kill cells as they arrive or leave someone
     
  5. Aug 30, 2009 #4

    Dale

    Staff: Mentor

    In order to kill a cell you need a certain current density. Static electricity discharges have a very high voltage, but a very low current, so they generally won't kill cells significantly.
     
  6. Aug 31, 2009 #5
    But enough to make you feel a little sting. In the certain region where the spark is produced the current density is quite high. But it's "instantaneous" (very very sudden) therefore no more harm is caused.
     
  7. Aug 31, 2009 #6

    Andy Resnick

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    Hang on, this is a bit more involved, I think.

    Clearly, damaging the epidermal skin layer (which is mainly dead keratin) is different from triggering a sensory nerve. Apparently, one can produce a pain sensation by applying a localized electrical stimulus (Bishop, Physiol. Rev 26, 77-102, 1946), but I don't know if the specific mechanism has yet been elucidated.
     
  8. Aug 31, 2009 #7
    So does skin cell usually get killed in the person who discharges causing the sting? If so how does that work because I've tried to shock other people but I've always felt the sting while the other person said they didn't feel anything
     
  9. Aug 31, 2009 #8

    Moonbear

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    Pain perception is through bare nerve endings in the dermis of the skin. It would take only a very tiny stimulus to "trigger" them without any damage, and static electricity qualifies.
     
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