Potential ground and electric charge

AI Thread Summary
In electronics, ground is typically defined as having a potential of zero, treating the Earth as a large conductor. However, there is debate regarding the Earth's net electric charge, with some arguing it has no net charge and is instead surrounded by charged regions like the Van Allen Belts. The key property of ground is its ability to maintain a stable potential regardless of current flow, rather than its resistance. This stability allows for the practical designation of ground potential as zero in electronic circuits. The discussion highlights the complexities of grounding in relation to the Earth's electrical properties.
sami23
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In electronics it is customary to define the potential of ground (thinking of the Earth as a large conductor) as zero. Is this consistent with the fact that the Earth has a net electric charge that is not zero?
 
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sami23 said:
the Earth has a net electric charge that is not zero
Really? Do you have a reference for what the net charge on the Earth is?
 
In electronics it is customary to define the potential of ground (thinking of the Earth as a large conductor) as zero. Is this consistent with the fact that the Earth has a net electric charge that is not zero?

I don't think either of these statements are correct.

The Earth is not a large conductor.
The Earth has no net charge itself , although it is surrounded by a charged 'halo' known as the Van Allen Belts.

The fundamental (electrical/electronic) property of an Earth or ground is that it does not change potential for any current flow within the normal circuit parameters, not that it has low or high resistance.
It is this property that allows the benchmark potenttial to be declared 'zero' in electronics.
 

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