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Homework Help: Need some explanation

  1. Apr 27, 2004 #1
    Hi all,

    I'm stuck on this charge equation:

    Q=Q * e (-t/RC)
    = 780 * e (-9.8/3.3)
    I've got 40.03
    but the answer is 15200

    if I took away the negative sign from the equation then I'll be able to get 15200. but that should not be the way isn't it? can somebody advise me how should I go about with this?

  2. jcsd
  3. Apr 27, 2004 #2


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    Science Advisor
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    Gold Member
    Dearly Missed

    I'd say your answer is correct; then the amount of net charge is depleted exponentially from an initial level Q_{0}=780.
    It really depends on what your original equation is trying to model.
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