1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Capacitor homework problem

  1. Feb 18, 2005 #1
    A capacitor C1 carries a charge Q0. Is is then connected directly to a second, uncharged, capacitor C2.

    What charge will each carry now? Q1 = Q0C1/(C1 + C2); Q2 = Q0C2/(C1 + C2)

    What will be the potential difference across each?
    V = Q0 / (C1 + C2)


    I know that the formula Q = CV is used, but how do you manipulate it (other than V = Q/C) to get the answers in bold?

  2. jcsd
  3. Feb 18, 2005 #2


    User Avatar
    Homework Helper

    The voltage around the loop will be 0 in equilibrium, and whatever charge the second capacitor gets, the first one must lose. Does that help at all?
  4. Feb 18, 2005 #3

    Doc Al

    User Avatar

    Staff: Mentor

    Since the capacitors are connected in parallel, they have the same voltage (V). So the charges on the capacitors are: [itex]Q_1 = C_1V[/itex] and [itex]Q_2 = C_2V[/itex]. The total charge remains the same, so [itex]Q_0 = Q_1 + Q_2[/itex]. Solve for V.
  5. Feb 18, 2005 #4
    I think I understand what you're saying, but I don't know how to apply it to the questions.
  6. Feb 18, 2005 #5
    Oh, OK. Let me try it.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook