Electrical charge, current definitions

AI Thread Summary
Electrical charge is a fundamental property that comes in two types, positive and negative, with neutral charge representing a state of zero charge. Current is defined as the flow of electric charge between two points over time, often expressed as charge in motion. The existence of only positive and negative charges is a historical convention based on observed behaviors, such as attraction and repulsion. Neutral electric charge is recognized as a state where an object experiences no net force in an electric field. Overall, understanding electrical charge involves recognizing its conservation and the forces it generates, as described by Coulomb's law.
Logical Dog
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What is electrical charge?
is it a measure of the abundance of electrons within a system?

Current is defined as the amount of charge flowing between any two points in a system over a given period of time, correct?

but what is elctrical charge if possible to define it better/further. I am also confused as to how many types of charge there exist, our professer said neutral electric charge is also one type apart from positive and negative! is this correct?

I know that we don't know why there exists only negative and positive cahrges, and its hard to define what charge is but perhaps someone can explain in a better way, and is "neutral electric charge" a thing?

thanks for your time!
 
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Bipolar Demon said:
What is electrical charge?...I know that we don't know why there exists only negative and positive cahrges, and its hard to define what charge is
We made observations and did experiments to discover how the universe behaves, and we discovered is that there is something that is conserved, that comes in two flavors (which we arbitrarily label positive and negative), that like repels and unlike attracts, and that causes a force that obeys Coulomb's law. Now we need a name for that thing, and for historical reasons the name is "electrical charge".

is "neutral electric charge" a thing?
If something is attracted to a negatively charged surface we say that it has a positive charge, and if something is repelled by a negatively charged surface we say that it is has a positive negative charge. So what do we say about something that is neither attracted nor repelled by a charged surface?

We could say that its electric charge is zero, or that it has no charge, or that it is neither positive nor negative... Or we could say "neutral".
 
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Bipolar Demon said:
What is electrical charge?...I know that we don't know why there exists only negative and positive cahrges, and its hard to define what charge is
We made observations and did experiments to discover how the universe behaves, and we discovered is that there is something that is conserved, that comes in two flavors (which we arbitrarily label positive and negative), that like repels and unlike attracts, and that causes a force that obeys Coulomb's law. Now we need a name for that thing, and for historical reasons the name is "electrical charge".

is "neutral electric charge" a thing?
If something is attracted to a negatively charged surface we say that it has a positive charge, and if something is repelled by a negatively charged surface we say that it is has a positive charge. So what do we say about something that is neither attracted nor repelled by a charged surface?

We could say that its electric charge is zero, or that it has no charge, or that it is neither positive nor negative... Or we could say "neutral".
 
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I think I liked it more the second time around. :wink:
 
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sophiecentaur said:
I think I liked it more the second time around. :wink:
its alright, anyone taking their time out to help me gets my likes...no matter how many replicated posts :P
Nugatory said:
and if something is repelled by a negatively charged surface we say that it is has a positive charge.
I also think Mr Nugatory means if something is repelled by a positively charged surface it is positively charged!
 
Bipolar Demon said:
I also think Mr Nugatory means if something is attracted to a positively charged surface it is negatively charged
Yes. That is the convention we have decided upon - toss of a coin which way round it turned out.
 
Bipolar Demon said:
I also think Mr Nugatory means if something is repelled by a positively charged surface it is positively charged!

I've left the duplicate post up because everyone seems to be having so much fun with it... And yes, of course I meant negative repels negative, positve repels positive, and negative and positive attract one another... A hazard of typing too fast...
 
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Are you positive about that?
 
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Bipolar Demon said:
What is electrical charge? Is it a measure of the abundance of electrons within a system?
Surplus/deficit of electrons is also an acceptable working picture.
Bipolar Demon said:
Current is defined as the amount of charge flowing between any two points in a system over a given period of time, correct?
The generic definition is charge in motion. In the particular sense, current is the amount of charge moving past a point divided by time (I=Q/t).
 
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