The variation of potential energy of harmonic oscillator is as shown in figure. The spring constant is
1×102N/m
150 N/m
0.667×102N/m
3×102N/m
Total potential energy = 0.04 JResting potential energy =0.01 JMaximum kinetic energy =(0.04–0.01)=0.03J=12m ω2a2=12ka20.03=12×k×2010002k=0.06×2500 N/m=150 N/m