A sphere of mass m = 2.5 kg can move across a horizontal, frictionless surface. Attached to the sphere is an ideal spring with spring constant k = 27 N/m. At time t = 0 the sphere is pulled aside from the equilibrium position, x=0, a distance d = 12 cm in the positive direction and released from rest. After this time, the system oscillates between x = ± d.

Determine the magnitude of the force, in newtons, required to initially displace the sphere d=11 cm from equilibrium