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Homework Help: Find Amperage knowing # electrons and time

  1. Feb 20, 2005 #1
    Hi, I've been having some problems with a hw question. In the problem it tells me the resistance of a resistor, and how many electrons pass through it in a given time. t = 5min. #e = 4.4E21. I need to find V.

    So, I need to find I since I know R.

    How do I do this? The only formula I could find was I = delta(Q)/delta(t). This gives me a huge value for I along the lines of 1.5E19, which can't be right, can it?

    Thanks a bunch,
    Brad
     
  2. jcsd
  3. Feb 20, 2005 #2
    Look at the units of Amps.
    Coulombs per sec
    How many electrons are in a Coulomb?
     
  4. Feb 20, 2005 #3

    dextercioby

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    What's with "1.5E19"...?What does it mean...?

    Daniel.
     
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