1. The problem statement, all variables and given/known data The problem is as follows: A 10 kg object and a 20 kg object are hung on a pulley system. Find the acceleration of each object. 3. The attempt at a solution I have already drawn the free-body diagrams, but I am confused as to where friction occurs in this problem. I have written out an equation for the first object - FNET=sigma F=T-W+a. I'm following Newton's Second Law, but how can I make what I have already written equal to ma if a is already in the first part of the equation? Also, how do I include friction, if it is necessary? Any help would be greatly appreciated.