1. The problem statement, all variables and given/known data https://dl.dropbox.com/u/66988308/Capture.JPG [Broken] 2. Relevant equations V=rW 3. The attempt at a solution I tried to plug in the forumla , and algebras but I keep getting rc/rf as answer instead of rf/rc as the book says. Work: Vf=(rf)W W=Vf/rf W=Vc/rc Vc/rc = Vf/rf (Vc)(rf) = (Vf) (rc) (Vc)(rf) / (Vf) (rc)= 1 Im not sure if this is the right track. Thanks for any advice.