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Homework Help: Charging a Defibrillator

  1. Nov 24, 2008 #1
    **EDIT: I solved the second part of the problem, I just need help on the syntax for the 2 equations of q(t) and I(t).

    1. The problem statement, all variables and given/known data

    http://img262.imageshack.us/img262/2139/phys1xf8.jpg [Broken]

    2. Relevant equations

    First Part:
    q(t) = Q(1-e-t/RC)
    I(t) = (emf/R) e-t/RC

    3. The attempt at a solution
    For the equations of q and I as functions of time, I basically plugged in all the numbers and WebAssign is telling me that it's wrong. I'm not sure what I'm doing wrong -- any help would be appreciated.

    Please help. :(
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Nov 25, 2008 #2


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    Staff Emeritus
    Science Advisor
    Homework Helper

    Just a guess, but they might want you to include units in your expressions for q and I, including the 1.7s in the exponential. They had provided the units in the previous answers, but not for those.

    Your numbers for q and I look right to me. I get something slightly different for (a).
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