1. The problem statement, all variables and given/known data I'm doing a lab where a known mass is suspended by a spring. All that is known is the mass of the weight used and the length of the elongation of the spring, and I need to find the elastic potential energy of the spring and the spring constant, K. 2. Relevant equations (formatted text links aren't clicking for me?) Elastic PE = 1/2Kx^2--x normally applies to the elongation of the spring though it is extending in the y direction in this case Gravitational PE = 9.81mh GPE + EPE = Total PE/KE (energy is assumed to be conserved) 3. The attempt at a solution The problem is I have two variables and no way I can see to substitute for one of them to simplify the equation, so I don't know how to isolate a spring constant or the elastic potential energy.