1. The problem statement, all variables and given/known data Please help, Ive been struggling with this question for so long! We havent done internal energy so im not sure even where to really begin? A 10.0 kg block is dragged over a rough, horizontal surface by a 76.0 N force acting at 20.0° above the horizontal. The block is displaced 3.50 m, and the coefficient of kinetic friction is 0.300. What is increase in internal energy of the block-surface system due to friction?