1. The problem statement, all variables and given/known data This is a question that the teacher gives every week that we do in class. He gives the parameters without the actual numbers a week before so we can prepare. The teacher will give: - the masses for both blocks (different) - the coefficient of friction for both blocks (different) - the applied force on Block A Question (what we have to figure out): What force is Block A exerting on Block B? http://img580.imageshack.us/img580/7968/85935850.png" [Broken] 2. Relevant equations Symbols weren't working for me but I'm assuming these equations are relevant: coefficient of friction = Net Force / Normal Force and Fnet = mass * acceleration 3. The attempt at a solution I'm not sure how to go about at this. I would have to specify some numbers before I try. I would have to find all the forces acting on both objects first (one force would be the mass, one force would be the friction, and one would be the applied force for Block B). After that, I have no idea what to do.