College Physics with MasteringPhysics 7th Edition by Jerry Wilson,Anthony Buffa,Bo Lou

Exercise 29

For the spring in Exercise, how much mass would have to be suspended from the vertical spring to stretch it (a) the first 6.0 cm and (b) the additional 2.0 cm
Exercise
A particular spring has a force constant of 2.5 × 10 3 N/m. (a) How much work is done in stretching the relaxed spring by 6.0 cm (b) How much more work is done in stretching the spring an additional 2.0 cm