A 60-N sledge hammer shown in the figure strikes the 90 N wood block which is at rest on the coil spring. The striking velocity of the hammer is 12m/sec and the block and hammer are assumed to remain in contact after striking. What is the scale of the spring if the blow causes the spring to be compressed 60mmm? Answer in N/mm and in 2 decimals.

A 60-N sledge hammer shown in the figure strikes the 90 N wood block which is at rest on the coil spring. The striking velocity of the hammer is 12m/sec and the block and hammer are assumed to remain in contact after striking. What is the scale of the spring if the blow causes the spring to be compressed 60mmm? Answer in N/mm and in 2 decimals.