1. The problem statement, all variables and given/known data A 0.580Kg wood block is firmly attached to a very light horizontal spring. It is noted that the block-spring system (k=160N/m), when compressed 4.0cm and released, stretches out 0.9 cm beyond the equilibrium position before stopping and turning back. 2. Relevant equations Conservation of Mechanical Energy KEf+PEf=KEi+PEi and 1/2kx^2 3. The attempt at a solution Ok, What I tried to do is solve for the work of friction using (coefficient of friction)(Normal Force)(d)=1/2k(xf-xi)^2. However, I do not understand what the problem is asking as far as distances. I converted the distance to m but I still do not know what they mean by compressed for 4 cm. Does that mean they pushed it 4 cm forward. Let it go and it went past its resting point .9 cm. If so is .9 negative? or is 4 cm negative?