# Easy question: find the current

1. Apr 11, 2010

### faen

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

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. Apr 11, 2010

### kentigens

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.

3. Apr 11, 2010

### faen

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

4. Apr 19, 2010

### kentigens

hmm... its like really basic. just get familar with kirchoff's v and i law. u'll be fine