Am 17.05.2010 14:36, schrieb Warp:
>    Well, that's precisely what I'm talking about. You are somehow assigning
> some magical properties to the basic "U=RI" formula by making odd statements
> like "cattle fences have a limited amount of current".
>
>    If we solve how much current a certain voltage difference produces, it's
> I = U/R. Here the resistance 'R' is the resistance of the human body. If we
> assume that this resistance is the same in both situations, then the *only*

That's a wrong assumption already: Cattle fence "generators" and the 
mains have much different internal resistance; in the case of mains, the 
human body resistance is probably dominating, but with a cattle fence, 
the internal resistance is.

Also note that the cattle fence does /not/ actually produce DC, but 
rather a pulsed AC; with the pulses being very short and sharp spikes, 
each pulse is dominated by very high frequencies, at which currents tend 
to travel close to the surface of a conductor. If that conductor happens 
to be a human, this means that the pulse will travel close to the skin, 
staying clear of vital organs. (Unless one of these organs happens to be 
an artificial pacemaker or the like, which are usually implanted close 
to the skin.)


All in all, I'm pretty sure it's a combination of various effects that 
makes cattle fences much safer than mains current, so /any/ answer 
mentioning only a subset of these can be considered wrong when running 
in nitpicking mode.

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