Does Electricity Need a Complete Circuit? Exploring Basic Physics Questions

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A_Physics_Dummy
How did you find PF?
Via google search
Hi Folks.

I've been retired for a decade.

Waaaaay back in time (1980) I got an engineering degree; in other words, in the mid-70s I took three freshman physics courses: Laws of Motion; Electromagnetics; Relativity/Quantum Mechanics. I doubt that I remember anything at all from these classes, since I used little of it during my working career.

My motivation in seeking out and finding this forum was to re-educate myself about electro-magnetics by looking into the question: Does electrical flow require a complete circuit?

For the past many decades, I had assumed that the answer to the above question is No, but when doing internet search on the topic I find explanations regarding how various phenomena such as lightning (allegedly) comprise a complete E-M circuit.

So, this is my 'thing' this month, pretending that I still have a brain and can explore interesting, although extremely basic questions in physics.

I'm grateful to those of you who provide the forum and those of you who contribute with responses and answers to questions and discussions.

G.T.
 
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Without a circuit, electrons can still move, but the result is a charge buildup.
That charge build up pushes back on further electron flow (like charges repel).
 
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.Scott said:
Without a circuit, electrons can still move, but the result is a charge buildup.
Or a discharge.

A_Physics_Dummy said:
Does electrical flow require a complete circuit?
A potential charge difference will cause charges to move to balance the charge if they can. That will take a very short time before the difference is balanced again.

The way to keep the charges moving is to close the circuit so they are continually being dumped in at one end and taken up at the other.

I am a layperson as well, so my descriptions are clumsy.
 
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.Scott said:
Without a circuit, electrons can still move, but the result is a charge buildup.
That charge build up pushes back on further electron flow (like charges repel).
Thanks Scott!
 
DaveC426913 said:
Or a discharge.A potential charge difference will cause charges to move to balance the charge if they can. That will take a very short time before the difference is balanced again.

The way to keep the charges moving is to close the circuit so they are continually being dumped in at one end and taken up at the other.

I am a layperson as well, so my descriptions are clumsy.
DaveC, that's a great explanation. Thanks!