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Variable Voltage Source

  1. Feb 27, 2007 #1
    1. The problem statement, all variables and given/known data

    As the voltage in the circuit shown below is increased (but not to the breakdown voltage), the capacitance


    a. increases.

    b. decreases.

    c. does not change.

    d. increases, decreases, or does not change, depending on the charge on the plates of the capacitor.

    e. does none of these.

    2. Relevant equations

    C = Q/V or C = (epsilon_0*A)/(d)

    3. The attempt at a solution

    If the voltage increases at a specific rate, then the charge would also increase since Q and V are directly proportional and the ratio between the two is a constant. Therefore, the capacitance does not change????

  2. jcsd
  3. Feb 27, 2007 #2
    The capacitance should remain the same as it is a function of geometry and the material between the plates.

    C = (epsilon * A) /d
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