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Integration Problem

  1. Jun 1, 2008 #1
    Hey everyone. This has been really bugging me for 4 hours now, and I cannot figure out where I am going wrong. If anyone can help me that would be greatly appreciated.

    The current flowing through a capacitor is:

    I = Ioe^-(kt)

    Io = 2 amps
    k = 0.2s
    T = time

    Find the charge flowed after the first 5 seconds

    Q = [tex]\int[/tex] I dt

    [tex]\int[/tex] 2e^-(0.2t) dt

    = 1/-0.2e^-(0.2t)

    = -10e^-(0.2t)

    [tex]\int[/tex] -10e^-(0.2t)

    [ -10e^-(0.2t)] = {-10e^-(0.2x5)} - {-10e^-(0.2x0)}

    = -10e^-1 - 0

    Then I end up with a negative number for Q . If anyone could point me in the right direction i'd be thankful .
  2. jcsd
  3. Jun 1, 2008 #2
    Your mistake is: e^0 does not equal 0, e^0 equals 1.
  4. Jun 1, 2008 #3
    Wow, I can't believe I made a mistake that simple, lol

    Thanks for your help! You really helped me out there!
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