1. The problem statement, all variables and given/known data http://img2.imageshack.us/img2/6536/physics1.png [Broken] 2. Relevant equations I = V/R, R = R1+R2+R3+... 3. The attempt at a solution 2R+R=3R V/3R this is an SAT II physics practice question, i just want to grasp this concept so im asking for an explanation, i.e. why this is a series circuit (or not?) oh and how do i know to treat the section with the 1/2 R's as a parallel circuit and not the entire right side? dont they both have parallel resistors? how do i differentiate for circuits in general?