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Homework Help: Introductory lvl circuit analysis problem

  1. Jun 28, 2013 #1
    1. The problem statement, all variables and given/known data

    Your factory is building RC low-pass filters using 10-6 F capacitors and 1k Ohm resistors. Suddenly the worldwide supply of capacitors dries up and you now have to build filters with the same electrical characteristics but you have to use inductors and resistors rather than capacitors and resistors. If you want to continue using your supply of 1k Ohm resistors, what value inductors should you use to build low-pass filters with the same characteristics as the RC filters you were building?

    2. Relevant equations


    3. The attempt at a solution

    I'm looking for an equation to solve this problem but I've none in my notes. The answer is in Henry (i.e. we are looking for inductor value). Can someone kindly help me understand and solve this problem? TIA!
  2. jcsd
  3. Jun 28, 2013 #2

    The Electrician

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  4. Jun 30, 2013 #3
    I did have those RC and RL equations in my notes, but I don't understand how to get the value of L from C and R. The answer is 1H btw.
  5. Jul 1, 2013 #4

    The Electrician

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    Figure out what the corner frequency is for the R-C low pass. Analyze the L-R low pass; it will have to use the same value of R. Figure out what value of L will give the same corner frequency.
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