A particle free to move along the x-axis has potential energy given by U(x) = K(1-〖 𝑒〗^(−𝑥^2 )) for −∞ ≤x≤ +∞ where k is a positive constant of appropriate dimensions . Then At point away from the origin ,the particle is in unstable equilibrium For any finite non zero value of x , there is a force directed away from the origin If its total mechanical energy is k/2 , then kinetic energy at the origin is k For small displacements from x=0 the motion is simple harmonic