An ideal spring hangs from the ceiling. A 1.65 kg mass is hung from the spring, stretching the spring a distance d = 0.0855 m from its original length when it reaches equiLiBrium. The mass is then lifted up a distance l = 0.0315 m from the equiLiBrium position and released. What is the kinetic energy k of the mass at the instant it passes back through the equiLiBrium position?
