Is the direction of electric field the direction of current?

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SUMMARY

The direction of the electric field is not the same as the direction of conventional current in general. The electric field drives the motion of electrons, which flow opposite to the direction of the electric field. However, in conductive materials, the direction of the current and the electric field align and are proportional, as described by Ohm's Law. Special cases, such as anisotropic materials like graphite, demonstrate that current density may not always align with the electric field direction.

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  • Understanding of electric fields and charge flow
  • Familiarity with Ohm's Law
  • Knowledge of conventional current vs. electron flow
  • Basic concepts of anisotropic materials in electrical conductivity
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  • Research the behavior of electric fields in anisotropic materials
  • Examine the differences between conventional current and electron flow
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StevenJacobs990
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Is the direction of electric field save as the direction of (conventional) current?
 
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StevenJacobs990 said:
Is the direction of electric field save as the direction of (conventional) current?

no, it's in the direction of charge flow ... electron direction. It is the electric field that drives the motion of the electrons/charge
 
StevenJacobs990 said:
Is the direction of electric field save as the direction of (conventional) current?
@davenn is correct. In general the electric field and the current are not in the same direction.

However, in the special case of a current inside a conductive material the direction of the current and the direction of the E field are the same and they are proportional to each other. This is the meaning of Ohm's law
 
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davenn said:
no, it's in the direction of charge flow ... electron direction. It is the electric field that drives the motion of the electrons/charge
Careful here. Th direction of Positive charge is defined by the direction of the field. That is the direction of the conventional current. Signs need to be observed meticulously and that post doesn't make it as clear as it should. Anyone who is struggling will need to make a conscious effort to realize minus times minus is plus when doing the sums.
StevenJacobs990 said:
Is the direction of electric field same as the direction of (conventional) current?
I would say that is perfectly correct and that bringing electrons in is not relevant here. The sign of the particles carrying the current is something that comes in much later.
 
Dale said:
@davenn is correct. In general the electric field and the current are not in the same direction.

However, in the special case of a current inside a conductive material the direction of the current and the direction of the E field are the same and they are proportional to each other. This is the meaning of Ohm's law
I don't get this. Positive charges will flow from a positive plate to a negative plate. That is also direction of the Field, isn't it? It may be that electrons are carrying the charge but that doesn't affect the conventional current.
Did you have something else in mind? I'm sure you must have.
 
sophiecentaur said:
Did you have something else in mind?
I was thinking of free charges in vacuum, where you can have currents (charge velocity) without an E field (charge acceleration).
 
Dale said:
I was thinking of free charges in vacuum, where you can have currents (charge velocity) without an E field (charge acceleration).
That's a relief! :smile:
But I'm reading the OP and assuming it is a question about the everyday situations of circuits, currents, devices and PD, In any of those situations, charge will flow (or at least be displaced) in the direction of any net Electric field.
I think it's time to give the OP a chance to respond and give us a better clue about the level of his question.
 
jtbell said:
There are anisotropic materials (e.g. graphite) in which the resistivity is described by a tensor, and the current density at a point is not necessarily in the same direction as the electric field.

https://en.wikipedia.org/wiki/Elect...ty#Tensor_equations_for_anisotropic_materials

This is a rather advanced topic, though. I don't remember seeing it in an introductory textbook.
Yes. It's a scientific truth but does it help with the OP's question? Seasoned PF members don't always take not of the Code Letter, associated with the title. It's a B, in this case, meaning basic High School Level.
 

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