A 5.0kg block is put on top of a 6.5kg block. To cause the top block to slip on the bottom one, while the bottom one is held fixed, a horizontal force of at least 21.6 N must be applied to the top block. The assembly of blocks is now placed on a horizontal, frictionless table as in the figure.
Find the magnitude of the maximum horizontal force F that can be applied to the lower block so that the blocks will move together.
Find the resulting acceleration of the blocks.