1. The problem statement, all variables and given/known data Problem: http://img355.imageshack.us/my.php?image=a3physicsfa1.png 2. Relevant equations http://hyperphysics.phy-astr.gsu.edu/Hbase/Waves/powstr.html 3. The attempt at a solution Yeah, can someone help me exactly to find the velocity I need in order to plug it in to the equation? I tried figuring out with the velocity using wavelength and all, but that didn't work. I think I need to sue that forumula, but without knowing T, I'm stumped right now. Also, what exactly is the difference between the maximum speed of this wave, and the speed calculated from, let's say V = sqrt (T/(M/L)) ?