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So first at all this question isn't really about electrical engineering, but about electricity in general. However, I think this is the best place to ask, correct me if I’m wrong. Also I’d like to mention that my knowledge about electricity is very limited, especially my knowledge about alternating current.

While working in the garden today, I used an electrical mowing machine which is powered by standard 230 V AC. What I didn’t see, is that the extension cable I used, had a crack in the insulation wrap and some wires were exposed. However when I touched one of the exposed wires by accident, I felt a little “shock”, but it was way less hurtful than I would have expected from 230 volts.

My guess is, that I only touched one of the power wires, so the current tried to flow through my body to earth, but because I was wearing shoes with rubber soles I was insulated from earth very well and only a tiny amount of current was able to flow through me. Does this make any sense?

Also, if I had touched both power wires, or one power wire and the earth wire, I would have shortened the circuit with my hand and thus I would have gotten the “full load”, right?

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    \$\begingroup\$ Replace. The. Wire. \$\endgroup\$ – winny Aug 26 '17 at 19:15
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Yes, probably you were wearing well isolating shoes, so you got only small schock.

Yes, touching both wires would give you more current trough. It depends on how you touch these wires. The most dangerous is to touch with arm and leg, or just live wire and no shoes, since the current would pass through the heart. Let's say that current over 40 milliamps through heart would start to cause irreversible damage.

Touching both wires with two fingers is not so deadly, even if the fingers would be burnt to charcoal. Even touching with two arms is better than having passed the current from arm to leg.

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Your skin has resistance. Dry skin has a relatively high resistance resulting in a lower current.

If you would have had wet hands, or one of the strands punctured the top skin layer, you would have had a painful arm.

You were probably also wearing nonconductive shoes. Further limiting the current path.

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You may have been fortunate and only touched the neutral wire. The neutral wire carries the return current and is generally close to zero volts with respect to ground because at some point on the distribution system it is connected to the earthing system. Note that this is done at an approved point such as the utility distribution transformer or at the entrance to your property. You should never connect neutral and ground on any of your circuits.

schematic

simulate this circuit – Schematic created using CircuitLab

Figure 1. Cable resistance results in a voltage drop on the live wire and a voltage rise on the neutral wire.

If significant current is flowing in your extension lead or elsewhere on your property the neutral voltage will rise above zero. This may be what you (fortunately) felt. As the other answers explain the shock current will depend on many factors.

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A "full load" depends on a lot of factors, not least of which is whether you are cold, or hot and sweaty. Not to mention whether the current path is through a single hand, arm to arm or arm to ground.

Touching a live piece of metal can result in anything from a mild sting to death.

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