Three identical blocks are pushed across a table at constant speed. The hand pushes horizontally. Let the stack of two blocks be system A and the single block be system B. Now suppose the mass of each block is 2.5kg, the coefficient of kinetic friction between the bottom surfaces of the blocks and the table is 0.20, and the blocks are moving at 0.50 m/s. Determine the magnitude of each force. So for the first step I drew a FBD for both systems. For system A there is a Normal force pointing to the right, and Normal force and Kinetic Friction force to the left. There is also a Normal force pointing up and a weight force pointing down. For system B there is a Normal force pointing to the right and a Friction force to the left. There is also a Normal force pointing up and a Weight force pointing down. I was able to find that the weight for system A is 50N and the weight for system B is 25N. Normal force pointing up for system A is also 50N and for system B is 25N. I know the total force is zero because there is no acceleration but I am having trouble figuring out how to find the Normal force. I know I need to use F=ma and Fk=coefficient of friction x Normal force.