9. Extra: You have two disks lying flat on ice, one has a string wrapped around the outside edge which unravels as you pull, the other has a string attached to a peg in the center. The discs have equal masses and dimensions and are initially at rest. If you start pulling both strings at the same time with the same constant force, at some time t later which of the two disks has moved further? Or have they both moved the same distance? Explain