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Homework Help: Capacitance question What is C_eq?

  1. Oct 15, 2008 #1
    1. The problem statement, all variables and given/known data
    C2<C2<C3<C4 for the capacitor combination shown. What is C_eq?

    a) less than C1
    b) more than C4
    c) between C2 & C3
    d) less than C2
    e) any value since it depends on the voltage applied

    2. Relevant equations
    Capacitors in series: 1/Ceq = 1/C1 + 1/C2 +... 1/Cn

    3. The attempt at a solution
    The answer key says (a) but I don't see how that works. I plugged in some numbers, for example with 4, 3, 2, 1 for the four capacitors and 5, 4, 3, 2 and for the former it's between C2 and C3 but for the latter it's greater than C4 so it seems like (e) would be the better answer.

    Attached Files:

  2. jcsd
  3. Oct 16, 2008 #2


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    Staff Emeritus
    Science Advisor
    Gold Member

    The capacitor C1 has the least capacitance and the capacitor C4 has the most. You are neglecting to take the reciprocal of your answer. Notice that the equation you're using is for 1/Ceq.
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