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B Is the direction of electric field the direction of current?

  1. Jan 15, 2017 #1
    Is the direction of electric field save as the direction of (conventional) current?
     
  2. jcsd
  3. Jan 15, 2017 #2

    davenn

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    no, it's in the direction of charge flow ... electron direction. It is the electric field that drives the motion of the electrons/charge
     
  4. Jan 15, 2017 #3

    Dale

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    @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
     
  5. Jan 15, 2017 #4

    sophiecentaur

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    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 realise minus times minus is plus when doing the sums.
    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.
     
  6. Jan 15, 2017 #5

    sophiecentaur

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    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.
     
  7. Jan 15, 2017 #6

    Dale

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    I was thinking of free charges in vacuum, where you can have currents (charge velocity) without an E field (charge acceleration).
     
  8. Jan 15, 2017 #7

    sophiecentaur

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    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.
     
  9. Jan 16, 2017 #8

    jtbell

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  10. Jan 16, 2017 #9

    sophiecentaur

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    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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