Static Charge on human body

Discussion in 'General Electronics Chat' started by aamirali, Sep 24, 2012.

  1. aamirali

    Thread Starter Member

    Feb 2, 2012
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    Human body is of 100pf modelled as, & can be charged upto 4000-35000V. So why don't we feel shock. Shock when we get from touching metal contact, is very less compared to high volatge involved
     
  2. Audioguru

    New Member

    Dec 20, 2007
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    Calculate the extremely short duration it takes for the tiny capacitance to discharge.
     
  3. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    I've felt the shock and heard the "pop" from static discharge MANY..MANY times..
    Its just SO fast.. I've seen the blueish spark from it too all the time.
     
  4. Audioguru

    New Member

    Dec 20, 2007
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    The POP is because the air the spark travelled through is very hot and its expansion is faster than the speed of sound (breaks the sound barrier).
     
  5. crutschow

    Expert

    Mar 14, 2008
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    I was visiting New Mexico one summer where it was very hot and dry (very low humidity), and the motel I stayed in had a carpet in the hallway. Every time I walked down the hallway and reached to touch the doorknob I felt a significant shock as the built-up static charge in my body from the carpet discharged. It gave me enough of a jolt that I soon learned to hold a metal key in my hand to discharge the spark when I reached the door (holding the key seemed to reduce the jolt from the discharge, apparently because it was spread out over a larger area of my hand). The spark from that was quite visible and a few tenths of an inch long.
     
  6. Audioguru

    New Member

    Dec 20, 2007
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    I had some shoes with high-tech synthetic soles that prevented my feet from getting wet when it was raining. Here in Canada (before global warming) it got pretty cold in winter then the humidity was VERY low.

    I had a great time shuffling along a carpet and creating a lighning bolt with my key.
     
  7. aamirali

    Thread Starter Member

    Feb 2, 2012
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    So does that mean large current flow when body get discharged as voltage is very high, but time is very very small. that's why we don't get badly hurt.

    Like in picture tubes, voltage is very high, but current is very less, but even when it is placed near the gnd it makes spark.
    But voltage on human body is 4000-35000V, compared to picture tube. So why don't we feel that.

    Also we say that there is very less current in TV, even then it create such an spark how?????
     
  8. Audioguru

    New Member

    Dec 20, 2007
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    There is enough current in a CRT TV's high voltage to kill you. Keep away from it.

    I think that a static discharge from you has low current because its duration is so low that your skin does not have enough time to become a low resistance (from being burned) unless you are sweating.
     
  9. Austin Clark

    Member

    Dec 28, 2011
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