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faen
Apr11-10, 05:03 PM
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

http://img.photobucket.com/albums/v488/nikko9000/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..

kentigens
Apr11-10, 07:10 PM
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.

faen
Apr11-10, 07:38 PM
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

kentigens
Apr19-10, 05:38 PM
hmm... its like really basic. just get familar with kirchoff's v and i law. u'll be fine