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Homework Help: Do protons move?

  1. Feb 1, 2014 #1
    1. The problem statement, all variables and given/known data

    Hi , in the first chapters of my physics book states that positive charges don't move , but now this new chapter about curruent and resistance says that the direction of the current is the direction in which the positive charges flow or move . I'm confused :confused:
    Can someone explain please? , I don't need a scientific explanation because that would confuse more:frown: , just a simple answer because I'll have an exam soon .Thanks :smile:
  2. jcsd
  3. Feb 1, 2014 #2
    protons do move and current is the flow of negatively charged particles electrons... :) not the positive charge.
  4. Feb 1, 2014 #3


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    When I first read the title to this thread I wanted to respond "Of course, protons move! I just moved a lot of them when I picked up this laptop computer."

    But I see you are asking a serious question. You are asking specifically about "charge" moving in an electric line, right? "Charge" is not the same as "protons" or "electrons". If the electrons move in one direction, then a negative "charge" is moving in that direction while a positive "charge" is moving in the opposite direction, even though no actual "protons" may move. It was, I believe, Benjamin Franklin who decided to declare that current move in a particular direction and, from the point of view of some physical matter actually moving, he got it wrong! Of course, he did not know anything about "protons" or "electrons". He was working with static electricity generators and, seeing a spark jump between his finger and the generator, assumed something was coming from the generator to his finger, not realizing that the "electrons" were actually going the other way. On a larger scale, he assumed that lightning was something going from the clouds to the earth. In fact, it is more often electrons going from the earth to the cloud.
  5. Feb 1, 2014 #4
    Protons don't move. When they say a positive charge moves. Think of it as electrons moving the opposite way. Say if you have a piece of metal and one side has a positive charge, what this means is there is a deficiency of electrons and so the positive charge will repel and electrons will flow to disperse the positive charge.
  6. Feb 1, 2014 #5


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    Franklin didn't necessarily get it wrong. The idea that "electric current is the movement of electrons" is only true in metals. In liquids, gases, and some non-metallic solids, both positive and negatively charged particles move in opposite directions.

    But instead of worrying about all that detail, in different materials, we always define "current flow" to be positive in the direction that positive charges would move, even if there aren't any positive charges that are actually moving.
  7. Aug 4, 2016 #6
    Hi,i think proton don't move but we take the flow of current as the direction of flow of +ve charge and opposite to the flow of current is the flow of -ve charge.we take it so because at the time of discovery of current electron were not discovered,so that's why we take the flow of current as the movement of +ve charge :oldconfused::oldconfused::oldconfused::oldconfused::oldconfused:
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