What is the electric potential of Earth?

AI Thread Summary
The electric potential of Earth is considered to be zero with respect to infinity due to its negligible net charge. When a capacitor is discharged and one terminal is connected to Earth, that terminal will have the same potential as Earth, which is zero. If the capacitor's terminals are shorted, a brief current will flow until the discharge is complete. After disconnecting the terminals, both will have a potential relative to infinity, but if they are identical in size, their potential will be half that of Earth. The discussion emphasizes that without a net charge, Earth maintains a potential of zero.
morangta
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What is the potential of Earth with respect to (wrt) infinity (C=710uF)? I am assuming that infinity is the correct reference here.

Suppose a capacitor that's normally used in an electric/electronic circuit is
a) discharged by connecting its two (2) terminals.
b) then they are disconnected and the capacitor is held in dry air.
c) then terminal 1 is connected to Earth, and is disconnected from Earth.

Does this terminal 1 then have the same potential wrt infinity as Earth? Is charge then residing on the plate of terminal 1? What is then the potential of the other plate (terminal 2) wrt infinity and wrt terminal 1?

Then if this capacitor's terminals are shorted together, is there a brief current flow? If the terminals are disconnected after the discharge current stops flowing, do both terminals have a potential wrt infinity? If the terminals are identical in size, is their potential now 1/2 that of the earth?

I hope these questions make sense. Please explain why if they don't.

Thanks for reading. Please let me know the answers if you know what they are.

Please excuse me if I have posted this before. I sometimes forget.
 
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Regardless of the capacitance of the earth, since it has essentially 0 net charge its potential is 0 wrt infinity. The only time that you would get a significant potential wrt infinity is if you gave it a net charge.
 
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