A block of mass 2 kg attached to a spring lies on a flat surface. When the block is pulled 5 cm to the right a force with a magnitude of 300 N is need to hold it in place. What is the work done by the spring when the block moves from x = 10 cm to x = 12 cm. Express your answer in joules.

Question

A block of mass 2 kg  attached to a spring lies on a flat surface.    When the block is pulled 5 cm to the right a force with a magnitude of 300 N is need to hold it in place.  What is the work done by the spring when the block moves from x = 10 cm to x = 12 cm.  Express your answer in joules.

bobpursley · Answer

k=300N/.05m=6000 N/m work done= PEmax-PEmin = 1/2 k (.12^2-.10^2)