1. The problem statement, all variables and given/known data A 0.620 kg wood block is firmly attached to a spring (k = 180 N/m). It is noted that the block-spring system, when compressed 0.050 m and released, stretches out 0.023 m beyond the equilibrium position before stopping and turning back. what is the coefficient of kinetic friction between the block and the table? 2. Relevant equations -(Wnc) = PEf - PEo + KEf - KEo 3. The attempt at a solution 1/2 kx2 = 1/2 mv2 + umgd This equation has two unknowns (u and v). I don't know any other equation to solve for the unknowns, so I'm stuck here... What other equation do I use?