1. The problem statement, all variables and given/known data Josh pushes a box of mass m which then travels on a horizontal surface. There is a coefficient of kinetic friction μ between the box and the surface. The box has speed v when it reaches x = 0 and encounters a spring. The box compresses the spring, stops, and then recoils and travels in the opposite direction. When the box reaches x = 0 on its return trip, it stops. Determine k, the spring constant, in terms of μ, m, g, and v. 2. Relevant equations 3. The attempt at a solution is the diagram I have drawn correct? If it is, I can use F=ma in x & y direction. However, how can I get V into this equation?