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This might be a stupid question but i am just a little confused about grounding/earthing. Specifically for example in a home when some electrical appliance faults, the current will go to ground since i assume it is then the path of least resistance/easiest path. From my understanding, this current then goes through ground and back to say the power pole ground and the current will go back into the circuit. However here are my questions:

  1. When the current flows through the ground and say i am standing 1 m away from the grounding pole, why isn't it possible for some of that current to go back through my body (assuming i was touching something positive in this scenario)? Is it since the human body is of a much higher resistance when compared to ground? (~100000 Ohms compared to around 7 Ohms).

  2. When current goes through the ground pole from a house in this scenario, why does it go back to say the power pole ground, rather then the neighbors ground pole as it is closer? Is it since the neighbors ground is on a different circuit?

  3. When current goes to ground through the house ground pole, it does go back to the power pole ground pole right? Then the current will go back into the power pole circuit or no? I am a bit confused as where the current goes after it goes to the ground?

4. Updated Question: If the houses are on the same transformer, if they both faulted at the same time, where does the current go then. Does it go to ground, then house 2 goes to house 1 then goes to the power pole ground?

Also Is it bad for the ground current to go back through to the source current? As in typically inst the fault current caused much higher or not typically for a household appliance failing like a toaster?

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  • \$\begingroup\$ (1) why do you think that it does not go through your body? .... (2) how do you know that it does not go through the neighbor's ground pole? ... why do you think that the neighbor's ground is on a different circuit? \$\endgroup\$ – jsotola Feb 2 at 22:42
  • \$\begingroup\$ I am not sure this is why i am asking these questions? \$\endgroup\$ – I have no clue Feb 2 at 22:46
  • \$\begingroup\$ then ask questions that do not indicate prior assumptions ..... for instance instead of why isn't it possible for some of that current to go back through my body? which says that the current does not flow through your body and you want to know why not, ask does some of that current flow through my body? \$\endgroup\$ – jsotola Feb 2 at 22:59
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  1. ... why isn't it possible for some of that current to go back through my body ...

It will only pass through your body if it presents an alternate path back to the source - the transformer, in this case.

  1. ... why does it go back to say the power pole ground, rather then the neighbors ground ...

schematic

simulate this circuit – Schematic created using CircuitLab

Figure 1. The ground current will return to the source.

Because it returns to the source. Current flows in a circuit so if your neighbour's pole transformer is separate to yours then there is no current coming from it so there will be no current returned to it.

  1. When current goes to ground through the house ground pole, it does go back to the power pole ground pole right?

Correct.


From the comments:

When it goes through the power pole ground, it goes back into the circuit right, back to the source?

Correct. Take a simple example when all appliances are off in both houses. No current is flowing from either transformer. Now a fault occurs in your house and a current of, say, 10 A flows from the live wire to your earth connection.

Q. Where has the current come from?
A. Your transformer.

Q. Where does the current return to (through the ground)?
A. Your transformer.

It has to be like this because current flows in a circuit.

Note that even though your neighbour's transformer has an earth connection no current will flow through it because there is no current flowing out on the live wire.

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  • \$\begingroup\$ Thanks, when it goes through the power pole ground, it goes back into the circuit right, back to the source? \$\endgroup\$ – I have no clue Feb 2 at 22:59
  • \$\begingroup\$ See the update. \$\endgroup\$ – Transistor Feb 2 at 23:08
  • \$\begingroup\$ @jsotola: I addressed that in the original answer under point 2. But thank you for the emphasis. \$\endgroup\$ – Transistor Feb 2 at 23:08
  • \$\begingroup\$ Thankyou, can i ask where does the current go if the houses are on the same transformer (see updated question) \$\endgroup\$ – I have no clue Feb 2 at 23:18
  • \$\begingroup\$ It should be clear to you by now that it must return to the transformer that supplied it. \$\endgroup\$ – Transistor Feb 2 at 23:21
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Electrons always take all possible paths. For AC, those paths will include charge movements caused as electric fields rise and fall.

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