[TriEmbed] Current & Voltage

[Shane Trent]

Brian,

Mythbuster's claims you only need 6 mA across the heart to induce cardiac
arrest. The bathtub is dangerous because of the low resistance from the
massively parallel connection between your body and the water. Jewelry
(rings, metal watch bands) can also greatly increase chance of
electrocution because of the intimate skin contact and likelihood of saline
perspiration under the ring/watch band. Another factor with rings/watches
is the possibility of the current flowing across the chest cavity via the
opposite arm or leg.

Rings and watches can also be dangerous around low voltage, high current
power sources (link a car battery). A car battery will melt a chunk out of
the tip of a screw driver in a flash if it shorts the terminals (hundreds
of amps). That much current flowing through a ring or metal watchband could
product serious burns or cost you a finger.

http://www.discovery.com/tv-shows/mythbusters/videos/appliances-in-the-bath-minimyth/

Shane


On Thu, Jul 9, 2015 at 11:40 AM, Carl Nobile via TriEmbed <
triembed at triembed.org> wrote:

> Brian,
>
> Okay, there three things to take into account and you forgot to mention a
> big one--resistance. In order for a 5V 850mA power supply to be able to
> kill you your body resistance (assuming 700 mA) would need to be 7.14 ohms.
> This is practically a dead short, which your body could never be even if
> soaking wet. The link below indicates that you only need 200 mA under the
> proper circumstances through the heart to become horizontal. So, even under
> this situation your body would need to exhibit a total resistance of 25
> ohms, this would still be difficult to happen. So this is why high voltage
> is so dangerous, because you need the fairly high voltage to, so to speak,
> punch through your body resistance to end up with a mere 200 mA to go
> through your heart.
>
> Read this link http://hypertextbook.com/facts/2000/JackHsu.shtml
>
> So, this all depends on body resistance and the voltage. The current does
> the killing, but is not so important when it comes to ease of death. Check
> the link below on WikaPedia it kind of explains the whole thing.
>
> Body resistance link https://en.wikipedia.org/wiki/Electric_shock
>
> Carl
>
>
>
> On Thu, Jul 9, 2015 at 11:00 AM, Grawburg via TriEmbed <
> triembed at triembed.org> wrote:
>
>> I know it's always, "it's the current that will kill you, not necessarily
>> the voltage", but surely there is a reasonable way to determine what the
>> "killing" combination is.  I've got a book that says 700 mA could do you in
>> if it finds a path through your heart.  Is this really suggesting that if I
>> take the 5VDC, 850 mA power supply I use for my Raspberry Pi, hook one lead
>> to my big toe and the other lead to my ear lobe I may end up dead? When we
>> discuss current & voltage in my RPi class next week I'd like some more
>> information to pass on.
>>
>>
>> Thanks,
>> Brian Grawburg
>>
>>
>>
>>
>>
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>
>
>
> --
>
> -------------------------------------------------------------------------------
> Carl J. Nobile (Software Engineer)
> carl.nobile at gmail.com
>
> -------------------------------------------------------------------------------
>
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-- 
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