1. The problem statement, all variables and given/known data The staples inside a stapler are kept in place by a spring with a relaxed length of 0.115 m. If the spring constant is 51 N/m, how much elastic potential energy is stored in the spring when its length is 0.150 m? Ok, so: Relaxed length= 0.115 m k= 51 N/m x= .150-.115= .035 m 2. Relevant equations PE elastic = 1/2kx^2 3. The attempt at a solution I did PE elastic = 1/2(51)(.035)^2 and got 0.031 Joules, but this doesn't seem correct. Am I doing something wrong?