1. The problem statement, all variables and given/known data A 0.26 kg mass attached to a spring undergoes simple harmonic motion with a period of 0.84 s. What is the force constant of the spring? 2. Relevant equations T = 2*pi*SQRT(m/k) 3. The attempt at a solution I know this is supposed to be an easy question, but for some reason I can't do it. Here is what I got (which is not right): T = 2*pi*SQRT(m/k) and to solve for "k": K = 2*pi*SQRT(m)[whole thing divided by .84 seconds] = 3.814 N/m Ok, so what am I doing wrong? Thanks!