In experiment 1, two blocks of identical mass are pushed together with a force of magnitude F over a time interval deltaT. In experiment 2, the same force is applied to the same blocks over the same time, except there is a spring (initially at equilibrium) between the blocks. Is the NET EXTERNAL WORK done on the system of the two blocks and spring the same, greater than, or less than, that done in experiment one (to the system of the two blocks)? W=Fx It seems to me as though the work ought to be less, because the same force is applied and the spring will cause the blocks to have less displacement. Because W=Fx, and F is constant and x is getting smaller, W should get smaller. Am I right, or is the same amount of work done to the system?