A block of mass 0.40 kg slides at 0.30 m s⁻¹ along a horizontal surface and hits a spring; the speed of the block becomes zero when the compression of the spring is 8.0 cm.

The variation of the compression x of the spring with the force F applied to the spring is shown in Fig. 3.2.

Assume that the elastic potential energy of the spring when its compression is 8.0 cm is equal to the initial kinetic energy of the block.

Use your answer in (b)(i) (the initial kinetic energy) to calculate the maximum force F_MAX exerted on the spring by the block.