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Homework Help: Easy question: find the current

  1. Apr 11, 2010 #1
    1. The problem statement, all variables and given/known data

    Can somebody please explain to me what i did wrong here? Got exam tomorrow and it would probably be usefull to know.. Thx

    skann0006.jpg

    2. Relevant equations

    axb = a*b/(a+b)

    3. The attempt at a solution

    First i tried finding the voltage over 1.5R x R.. Then divide that voltage over R to find the current over R... For some strange reason this is wrong. Plz someone help me to understand why..
     
  2. jcsd
  3. Apr 11, 2010 #2
    treat the 1.5R and R as parallel. then in series with the 0.6R to get the overall resistance. current going through 0.6R = voltage/overall R. Then the same current split into the 1.5R and R, calculate.
     
  4. Apr 11, 2010 #3
    nice, thx a lot. Now i got further :)

    However if u would be able to point out what i assumed wrong in my first attempt itd be apreciated as well, so i dont happen to do a similar mistake again
     
  5. Apr 19, 2010 #4
    hmm... its like really basic. just get familar with kirchoff's v and i law. u'll be fine
     
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