Hello everyone, i have the following two part prompt and im having a difficult time with the second part. Here is first part of the prompt, A block of mass 0.528 kg slides with uniform velocity of 4.15 m/s on a horizontal frictionless surface. At some point, it strikes a horizontal spring in equilibrium. If the spring constant is k = 25.5 N/m, by how much will the spring be compressed by the time the block comes to rest? I found the spring compression to be 0.59m using Energy(initial)+Work(non conserved)= Energy(Final) The second part is as follows, What is the amount of compression if the surface is rough under the spring, with coefficient of kinetic friction µk = 0.411? From what i learned in class i am supposed to stick to the concept used above, so I plugged in Kinetic friction for work as '-0.411d'. My professor made it known that d stood for the distance but I'm not sure where I can pull that information. I tried using 0.59 since that 'was' the distance travelled before friction was introduced but it didn't work out. Any help would be appreciated.