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In contrary to static electricity the mains electricity must return to the power plant. When I touch the live then the current flows through my body and the floor of my appartment and through soil to the nearest grounding point.

It seems to me that in most cases the resistance of the floor and soil would be much greater than that of my body. If the mains voltage is 230 V and the resistance between my feet and the grounding point is 10x higher than the resistance of my body then there should be 20V across my body which seems pretty harmless. However this is just a guess and I don't have the balls to perform the experiment :)

There might be also a small capacitance but I doubt it has significant effect at 50 Hz.

I can measure the resistance of my body with a multimeter as 500 kiloohm (wet fingers) to 1.5 megaohm (dry fingers) however it may change with voltage because liquids tend to do that. I might measure the resistance between some point on the floor and bare metal of the hot water radiator (it's grounded).

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    $\begingroup$ Look for help. You have a problem if you risk your life with dangerous, useless experiments like this. Seriously. $\endgroup$
    – my2cts
    Commented Jan 4, 2021 at 22:49
  • $\begingroup$ Maybe I wasn't clear enough. This is just a thought experiment not a real one. $\endgroup$
    – Puzzled student
    Commented Jan 4, 2021 at 22:56
  • $\begingroup$ Why don't you then think about shorting the live wire directly to the bathroom floor instead of across your body? Note that this is also dangerous, but less so. $\endgroup$
    – my2cts
    Commented Jan 4, 2021 at 23:01
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    $\begingroup$ The Wikipedia article on Electrical Injury addresses several factors that affect the likelihood of injury when touching a live wire. $\endgroup$
    – The Photon
    Commented Jan 4, 2021 at 23:05
  • $\begingroup$ my2cts: Sometimes people will tell you that wearing thick shoes will protect you from the shock. I was wondering about the point of the shoes. The resistivity of the floor is fairly high and I think a contact area will be a significant factor. We could reword the question to touching the floor with live piece of metal of the size of human foot. $\endgroup$
    – Puzzled student
    Commented Jan 4, 2021 at 23:11

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The answer isn't simple. One case might be safe, but another that doesn't seem to be much different can be dangerous. Voltage isn't the only thing you need to know. Wet hands/dry hands is an example.

As the Electrcal Injury article mentioned by The Photon says, things like current, duration, pathway, and medical condition matter.

For example, touching a novelty Plasma lamp is harmless. It runs at a high voltage. The thin glass envelope isn't a good enough insulator to prevent current from flowing through it. Even though the voltage is very high, the current is low. And it works at radio frequency. Current at that frequency doesn't penetrate into your body far enough to cause damage.

On the other hand, a neon sign power supply is deadly.

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