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Parallel Circuits

  1. Aug 17, 2011 #1
    Question: Determine the net resistance of 100 ohms, 250 ohms and 400 ohms connected in a parallel.

    I have no clue how to figure this out. I have read and reread the section in my book and it is not helping. Please help.
  2. jcsd
  3. Aug 17, 2011 #2
    Well what have you tried so far?
  4. Aug 17, 2011 #3
    1/Rp = 1/100 + 1/250 + 1/400

    I know the answer is:

    1/Rp = 60 + 24 + 15/6000 ohms
    Rp = 6000 ohms/99 = 61 ohms

    I just have no clue where these numbers are coming from!
  5. Aug 17, 2011 #4
    Well I haven't a clue how you got from your formula to your second line.

    I agree that your answer of 61 is close enough though.

    Can you not do the arithemetic involved in your first line?
  6. Aug 17, 2011 #5
    Your answer and the books answer are the same. They just multiply the fractions so there is a common denominator (However odd that denominator is)
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