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Homework Help: Impedance Problem

  1. Jun 12, 2013 #1
    1. The problem statement, all variables and given/known data

    A circuit consists of a 50nF capacitor in series with a 47kΩ resistor. An AC voltage of 120Vrms at
    350Hz is applied to the circuit.

    (a) Determine the current flowing through the circuit.
    (b) Sketch the impedance diagram for the circuit at this frequency.

    2. Relevant equations

    Xc , diagram , V = IZ

    3. The attempt at a solution

    First i found Xc = 1/2* pi* f * C

    Then i did impedence diagram to find z and then use V = IZ to find Z

    I got the answer: 2.51mA

    But why it says answer is : 3.545sin(700π+11^0)mA ????
  2. jcsd
  3. Jun 12, 2013 #2


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    Homework Helper

    That is wrong. Check your lecture notes or books.

  4. Jun 13, 2013 #3
    isnt it Xc = 1/ angular freq.* C ??
  5. Jun 13, 2013 #4


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    Homework Helper

    Xc = 1/ angular freq.* C means 1/angular frequency, multiplied by C. Use parentheses: Xc=-1/(ωC) and do not forget, that Xc is negative.

    Show your work in detail.

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