Halliday, Resnick & Walker — Force and Motion–II: Problem 61_SSM

A block of mass \(m_t = 4.0\text{ kg}\) is put on top of a block of mass \(m_b = 5.0\text{ kg}\). To cause the top block to slip on the bottom one while the bottom one is held fixed, a horizontal force of at least \(12\text{ N}\) must be applied to the top block. The assembly of blocks is now placed on a horizontal, frictionless table (Fig. 6.36). Find the magnitudes of (a) the maximum horizontal force \(\vec{F}\) that can be applied to the lower block so that the blocks will move together and (b) the resulting acceleration of the blocks.