1. The problem statement, all variables and given/known data A bloc of 0,2 kg is attached to a spring on a horizontal surface with no friction. (The other side of the spring is attached to a wall, so it doesn't move) The spring constant is 5 N/m. If we pull on the spring, we move it by 0,12 m from its natural position and we let it go after that (It has an initial speed of 0 m/s) What is the speed when we have a maximal compression 2. Relevant equations U=1/2*k*e^2 Kf+Uf=Ki+Ui 3. The attempt at a solution I get the following equation : 0,2v^2 + 5e^2 = 0,072 I don't know what is the maximal compression !