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Homework Help: A question involvingn safe working voltage and capacitors?

  1. Oct 19, 2011 #1
    1. Problem Statement
    Some capacitors are marked 48uF, safe working voltage 25V.
    Show how a number of these capacitors may be connected to provide a capacitor of capacitance:
    a) 48uF, safe wroking voltage 50V
    b) 72uF, safe working voltage 25V


    2. Relevant Equations
    obviously C total in parallel = c1 + C2... and 1 / C total in series = 1/ C1 + 1 / C2


    3. Attempt at the Solution
    for part a) i thought you could have two of the capacitors in parallel, followed in series by another two capacitors in parallel for b) i didnt really have a clue, but perhaps two in series? (im probably wrong!)

    the answers state that for part a) "two capacitors in series", such that V < 25V across each capacitor.
    for part b)"two capacitors in parallel with a single capacitor"

    what is the safe working voltage??
     
    Last edited by a moderator: Oct 19, 2011
  2. jcsd
  3. Oct 19, 2011 #2
    Hint: what is the safe energy in the original capacitor set up?
     
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