In the diagram given, you pull upward on a rope that is attached to a cylinder on a vertical rod. Because the cylinder fits tightly on the rod, the cylinder slides along the rod with considerable friction. Your force does work (W = + 100 J) on the cylinder–rod–Earth system (Fig. 8-23b). An “energy statement” for the system is shown in the diagram: the kinetic energy K increases by 50 J, and the gravitational potential energy Ug increases by 20 J.
The Attempt at a Solution
As far as I know, thermal energy is q=mcdT, but none of those values are given here.