A particle of mass m kg is attached to one end A of a model spring OA of natural length L=0.81m and stiffness K N/m. The spring is hung vertically with the end O fixed and end A attached to the particle, which moves in a vertical line. The particle's mass, stiffness and natural length of the spring are related to the expression KL=2mg, where g is the magnitude of the acceleration due to gravity. It is observed that when the particle is at its highest point during the motion, its distance below O is 1/2L.

Question

Using the law of conservation of mechanical energy, find the distance, in m, of the particle below O when it is at its lowest point during the motion.

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