In electrostatics, what is meant by positive charges?

In summary: This is not true, e.g., in semi-conductors, where rather the holes can make the conduction-charge carriers, and these are positive quasiparticles (though it's again not the positive ions in this case!).
  • #1
TheSecretPiePiece
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I am needing clarification for a concept. I understand that electrons carry a negative charge and that protons carry a positive charge. I also understand that a plastic rod picks up electrons when I rub it with a piece of wool. From the conservation of charge, the piece of wool must have a positive charge. Is this positive carried by protons, or is it a consequence of the loss of some electrons?
 
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  • #2
TheSecretPiePiece said:
From the conservation of charge, the piece of wool must have a positive charge. Is this positive carried by protons, or is it a consequence of the loss of some electrons?
They are the same thing. An excess of protons is the same as a deficit of electrons.
 
  • #3
TheSecretPiePiece said:
Is this positive carried by protons, or is it a consequence of the loss of some electrons?
Both. You aren't adding protons, if that's what you mean, just moving electrons somewhere else.
 
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  • #4
Ibix said:
Both. You aren't adding protons, if that's what you mean, just moving electrons somewhere else.
The protons in a material are fixed in pretty tight to the atoms - you are unlikely to be able to shift those little devils without a high energy particle beam. To get an object positively charged, you have to take away some electrons. The first few billion would come away fairly easily off a metal.

The net charge imbalance on an object involves only a very small fraction of the total charges (positive and negative) in all the atoms. To strip an electron from every atom in a gram of solid copper, say would involve colossal electric forces (think Inverse Square Law and Atomic distances!) and any object would just fly apart by repulsion.
 
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  • #5
sophiecentaur said:
The protons in a material are fixed in pretty tight to the atoms - you are unlikely to be able to shift those little devils without a high energy particle beam. To get an object positively charged, you have to take away some electrons.
Yes - that's what I meant.

OP - your question isn't well phrased. Charged objects are said to carry a charge. Protons always carry a positive charge, electrons always a negative one, and ordinary matter carries either a positive, negative, or no charge depending on whether it's got more protons than electrons or the other way around, or equal numbers. But protons aren't mobile in solids, while electrons can be - so any net charge a lump of matter has is a result of electrons being added or removed.

So the answer to your first option is yes - the positive charge is carried by the protons. And the answer to your second option is also yes - the net positive charge is due to you having removed electrons. I suspect that the latter is what you wanted to know.
 
  • #6
Ibix said:
Yes - that's what I meant.
I wasn't disagreeing with you - just amplifying your point. Of course, in a gas / plasma / ions in water, the positive charged ions are free to move so it has to be pointed out that the message only relates strictly to solids.
 
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  • #7
More precisely it relates to (solid) metals, where the positive ions define the "natural" restframe of the medium, and in this rest frame the conduction electrons make up the current.

This is not true, e.g., in semi-conductors, where rather the holes can make the conduction-charge carriers, and these are positive quasiparticles (though it's again not the positive ions in this case!).

By definition, in a plasma both the positive ions and the electrons move freely and both make up the electric currents (in the local rest frames of the fluid as a whole).
 
  • #8
I actually less nagtive chrage for
 

Related to In electrostatics, what is meant by positive charges?

1. What is the definition of positive charge in electrostatics?

Positive charge refers to the presence of excess protons in an atom or object, resulting in a net positive charge. In electrostatics, positive charges are attracted to negative charges and repel other positive charges.

2. How is positive charge different from negative charge in electrostatics?

Positive charge and negative charge are opposite types of charge in electrostatics. Positive charges have an excess of protons, while negative charges have an excess of electrons. They are attracted to each other and repel other charges of the same type.

3. Can objects have both positive and negative charges?

Yes, objects can have both positive and negative charges. This is known as having a net charge, which is the overall charge of an object. Objects can acquire a net charge through the transfer of electrons from one object to another.

4. How is positive charge created or generated?

Positive charge can be created or generated through processes such as friction, conduction, and induction. These processes involve the transfer of electrons, resulting in an object having an excess of protons and a net positive charge.

5. What are some examples of objects with positive charges?

Some examples of objects with positive charges include protons, the nucleus of an atom, and objects that have been rubbed against each other, such as a balloon rubbed against hair. These objects have an excess of protons and are attracted to negative charges.

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