1. The problem statement, all variables and given/known data Three pieces of string, each of length L, are joined together end-to-end, to make a combined string of length . The first piece of string has mass per unit length mu_1, the second piece has mass per unit length mu_1*4.00 , and the third piece has mass per unit length mu_1/4.00. If the combined string is under tension F, how much time does it take a transverse wave to travel the entire length 3L? Give your answer in terms of F, mu_1, and L. 2. Relevant equations v = sqrt(F/mu) T = position/velocity = 3L/v ?? 3. The attempt at a solution The answer is (7L/2)*sqrt(mu_1/F). I understand the sqrt portion, but I am having difficulty with the multiplicative factor. I thought the velocity would be: v = sqrt(F/mu_total), where mu_total = mu_1 + 4*mu_1 + .25*mu_1 = 5.25*mu_1 T = 3L/sqrt(F/5.25*mu_1) = 3L*sqrt(5.25)*sqrt(mu_1/F) How do I get the correct factor? Thanks.