Question

3-28E The force F required to compress a spring a distance x is given by F – Fo = kx where k is the spring constant and F, is the preload. Determine the work required to compress a spring whose spring constant is k== 200 lbf/in a distance of one inch starting from its free length where F-0 Ibf.Express your answer in both Ibf-ft and Btu.

Fig: 1

Fig: 2