1. The problem statement, all variables and given/known data We have an inclined plane, 20 degrees, with two blocks on it. The higher block (m2) is 15 kg and the lower block (m1) is 20 kg. A 200N force is applied to the blocks and they move up the inclined plane at a constant speed. What force does the 15 kg block exert on the 20 kg block? 2. Relevant equations F = ma 3. The attempt at a solution My thinking is as follows. The net force in the parallel direction must be zero since we have a constant speed. Therefore, the sum of the forces from blocks 1 and 2 must equal 200N. m1*g*sin(20) + m2*g*sin(20) = 200N We want the force that the higher block (m2) exerts on the lower block (m1). m2*g*sin(20) = 200N - m1*g*sin(20)... so we need to find 200N - m1*g*sin(20). This comes out to: 200N - (20kg)(-9.8 m/s^2)*sin(20 deg) = 200 - -67 = 267 N. Does this answer make sense to anyone? Thanks!