1. The problem statement, all variables and given/known data A 2kg mass and a 3kg mass are attached to a lightweight cord that passes over a frictionless pulley. The hanging masses are free to move. Choose coordinate systems for the two masses with the positive direction up for the lighter weight and down for the heavier weight. Find the acceleration of the smaller mass. 2. Relevant equations F=ma 3. The attempt at a solution Fnet = Ft-Fg = 3g-2g = g the tension force on the smaller mass is equivalent to the weight of the heavier mass, so the net force acting on the object is g (m1+m2)a=g a=1.96 m/s² I know this is the answer, but I'm not sure why. If we already know that the force on the object is g, why don't we just say g=2a and get a=4.9 m/s²?