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Homework Help: Capacitive reactance

  1. Mar 27, 2012 #1
    1. The problem statement, all variables and given/known data
    Now demonstrate how to calculate resonant frequency. Calculate the capacitive reactance for a 300uF capacitor in series with a 800mH inductor.

    2. Relevant equations
    f = 1/2pi(LC)^1/2
    Xc = -1/2pifC

    I urgently need this solution checked out for my BTech deadline. The question reads thus:

    3. The attempt at a solution
    where L = 800mH, C = 300uF

    f = 1/2pi(800 x 10^-3 x 300 x 10^-6)
    So, f = 10.3 Hz

    so, Xc =-1/2pi (10.27 x 300 x 10^-6)

    Will my final answer be expressed as a negative?
    Any suggestions will be appreciated.
    Thanks a lot in advance.
  2. jcsd
  3. Mar 27, 2012 #2


    User Avatar

    Staff: Mentor

    Technically capacitive reactance is a negative reactance, so best to express it so. Also be sure to assign it the appropriate units! Everything should have units :wink:
  4. Mar 27, 2012 #3
    So, my final answer is in ohms and negative. Aside from that, is my working okay? I feel its fine but its the determinant for a distinction or a merit.

  5. Mar 27, 2012 #4
    Thanks everyone. I take that as a yes! My sincere appreciation and gratitude.
    Last edited by a moderator: May 5, 2017
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