A 16# block on a 15* incline is released w/a F=30# pulling up at 30* to the Horiz. it's Vo=3ft./s and V=9ft./s after moving 2ft. up the incline. Determine the Work done by Friction. I have started by trying to find the Accel. but I do not know that it is going to help me. Anyone have any insight on this problem?