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Homework Help: Charge And current Of Electric. Explain something?

  1. Feb 9, 2006 #1


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    I today learn about chrage of electric and Arus/ current electrici? Im not really know in english cause mine is in Malay. I just want to know something that the calculation of Electricity

    Charge of electric formula is Q=nq : (C) columba correct me if im wrong.
    A electric current( not sure right pronounsation) formula is I=Q/t

    Example question that i want to ask y this happens.

    A charge if electric is 1 x 10^-9 C
    Find the number of electrons that flows every second ( i want to find how many electrons flows every 1 second)

    Answer :
    I = nq/t
    I/q = n/t
    (1 x 10^-9) / (-1.60 x 10^-19) = n/t
    n/t = 6.25 x 10^12 <----- It should be ( -6.25 x 10^12)

    but y izzit positif? I learn that if you count amount of electron in a object then its suppose to be neagatif as answer? My teacher said something about science term that there is no negatif value. Im not really sure wat it mean can some one explain more detail? If im wrong anything please correct is also. Thx :frown:
  2. jcsd
  3. Feb 9, 2006 #2
    You're talking about electrons, so the value that you were given for the charge has to be negative, since when does an electron have a positive charge? (positrons don't count). Also, it makes sense that it should be positive, since how can you have a negative number of electrons? It's simply a number, there are no units and it is not a vector quantity, so it should be positive. Hope that helps.
  4. Feb 9, 2006 #3


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    But if you count a electron wouldnt it will be negatif? but instead this case is positive unless you are counting a proton. Any other eplanation other then finchie_88 answer? Thx finchie_88 for your answer also.
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