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Homework Help: Charge that a battery transfers between two plates

  1. Mar 7, 2010 #1
    1. The problem statement, all variables and given/known data
    An AA battery (1.5 V potential) is connected to a parallel-plate capacitor having 6.00cm-diameter plates spaced 4mm apart. How much charge does the battery move from one plate to the other?

    2. Relevant equations
    V=Q/C
    C=A[tex]\kappa[/tex][tex]\epsilon[/tex]/d


    3. The attempt at a solution
    Plugged in values:
    C = (.03)2*(8.85*10-12)/.004 = 1.99*10-12
    Q = 1.5V * 1.99*10-12f

    Getting an incorrect answer for Q. Thoughts?
     
  2. jcsd
  3. Mar 8, 2010 #2
    You forgot a factor of [itex] \pi [/itex] in the formula for area.
     
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