text: There are only two relevant forces acting on the blocks. The force exerted by the spring which is pushing them apart, and the frictional force which is opposing the spring force.\n\nThe kinetic coefficient of friction is K\n\nThe Spring force = (3.85Newtons/meter)(0.08meters) = 0.308 Newtons\n\nThe frictional force on the left block = (9.8 Newtons/kg)(0.25kg)K = 2.45 K Newtons\n\nThe frictional force on the right block = (9.8 Newtons/kg)(0.50kg)K = 4.90 K Newtons\n\nThe initial acceleration of each block is initial force/mass. Note that the spring force on each block must be greater than the frictional force, or the block wont accelerate (acc=0).\n\nFor the left block, acceleration = (0.308 - 2.45 K) / 0.25\n\nFor the right block, acceleration = (0.308 - 4.90 K) / 0.5\n\nLets plug in the 3 different Ks\n\nk = 0, left block acc. = 1.23 m/s^2, right block acc. = 0.61 m/s^2\nk = 0.1, left block acc. = 0.25 m/s^2, right block acc. = 0.0 m/s^2\nk = 0.462, left block acc. = 0.0 m/s^2, right block acc. = 0.0 m/s^2