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Path of current through body?

  1. Jul 25, 2011 #1
    Wondering if anyone can help me with this.

    Trying to find out what path electrical current takes when it passes from one hand to the other on its way to earth. I know it goes up the arm, accross the chest and then down the other arm and out the hand to earth through whatever earthed object said hand is in contact with.

    But what i want to know, is GENERALLY, where in the arms and body the current travels? And i am talking about standard UK mains voltage. Does the current travel along the skin, or does it pass to the blood and muscle and travel trough that?

    On a side note, what is the GENERAL difference between the resistance of hard skin on the hands and soft skin on for example, the inner arm? I know moisture plays a big part. So just want to know a general range of what the resistances could be?

    Any answers would be greatly appreciated. Thanx
  2. jcsd
  3. Jul 26, 2011 #2


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    Wikipedia (Electric shock):
    "The NIOSH states 'Under dry conditions, the resistance offered by the human body may be as high as 100,000 Ohms. Wet or broken skin may drop the body's resistance to 1,000 Ohms," adding that "high-voltage electrical energy quickly breaks down human skin, reducing the human body's resistance to 500 Ohms.'"

    And for 220V, dry skin, 50Hz: ~1-2kOhm (5%-95%)

    There will be some skin effect, (see Wikipedia article of the same name) so the current density would fall approximately exponentially with depth if the resistance of the body were constant, but the tissues have a very complex distribution of conductivity. The low-resistance path is likely along major blood vessels and hence through the heart.
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