1. The problem statement, all variables and given/known data Consider the system shown in the figure (Figure 1) . Block A weighs 46.1 N and block B weighs 28.7 N . Once block B is set into downward motion, it descends at a constant speed. http://session.masteringphysics.com/problemAsset/1038576/6/YF-05-54.jpg A Calculate the coefficient of kinetic friction between block A and the tabletop μ= 0.623 B A cat, also of weight 46.1 N , falls asleep on top of block A. If block B is now set into downward motion, what is its acceleration magnitude 2. Relevant equations F=ma 3. The attempt at a solution ∑F in x direction of A: -F+T = ma -μ92.1+T = 92.2/ 9.8 a -.623(92.1)+T=9.4 a ∑F in y of A N-w = ma 92.2-9.4(9.8) = 0 ∑F in Y of B T-w T-2.93 (9.8) = 2.93 a T= 28.7+2.93a plug T into first equation: -.623(92.1)+28.7+2.93a = 9.4a -.623(92.1)+28.7= (9.4-2.93) a divide both sides ( -.623(92.1)+28.7) /9.4-2.93 = a gives me wrong answer, where did I go wrong?