1. The problem statement, all variables and given/known data I need to write an equation for the at rest at a stoplight. Each car bumps into the one in front of it until the first car in line gets bumped. 2. Relevant equations I found these equations for wave speed: V=√(T/(m/L)), where T is tension, m is mass, L is length and of course V=λf 3. The attempt at a solution But both those equations have a time factor, and I wasn't given any time information. All I know is that wave speed needs to approach infinity as x → 0, and wave speed approaches vo as x→∞ Any hints would be appreciated.