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Homework Help: Potential Difference

  1. Apr 9, 2010 #1
    1. The problem statement, all variables and given/known data
    Like I'm doing a problem right now which is too long to copy or paste here, its basically a circuit where there are 3 batteries in parallel, and in one of them, current is passing through the battery from the positive to the negative terminal (from high to low potential)..now I know that the potential difference is negative through this particular battery, but the thing I don't understand is why at this battery, it is at a higher potential than the other batteries whose currents flow from low to high potential...?? I don't know if I provided sufficient detail for you guys to understand it...
    basically i don't know what exactly a negative potential difference means...


    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Apr 9, 2010 #2
    First I want to tell you that positive terminals are in high potential. Current flows from high to low potential not from low to high potential.
     
  4. Apr 28, 2010 #3
    i wanna know how a negative potential is created in a power source......
     
  5. Apr 29, 2010 #4
    Electric potential at any point is defined as the amount of work done in bringing a unit positive test charge from infinity to that point against the electric field. So if any positive charge is there then it will repeal the unit positive charge and so we have work is needed and therefore it has positive potential but if negative charge is there then it will help or attract unit positive charge and thus has negative potential.

    Now in you case, electric current is mainly due to the flow of electron which is negatively charged and so you are confused. You also have to know that direction of flow of current is defined in two ways.

    (i) Electronic way
    (ii) Conventional way.

    Study this topics and everything will be clear.
     
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