Potential energy vs. position graph of a particle in a particular system is given and here PE is U = ax2. There is a non-conservative force also acting on the particle in such a way that the loss of mechanical energy due to its work is equal to four times of its distance travelled. Initially, the particle is at x = 10 m, has kinetic energy 36 J and moves towards origin. Find the kinetic energy (in J) of the particle when it reaches origin the second time.