College Physics with MasteringPhysics 7th Edition by Jerry Wilson,Anthony Buffa,Bo Lou

Exercise 80

One block (A, mass 2.00 kg) rests atop another (B, mass 5.00 kg) on a horizontal surface. The surface is a powered walkway accelerating to the right at 2.50 m/s 2. B does not slip on the walkway surface, nor does A slip on B's top surface. (a) Sketch the free-body diagram of each block. Use these to determine the force responsible for A's acceleration. Is it (1) the pull of the walkway, (2) the normal force on A by the top surface of B, (3) the force of static friction on the bottom surface of B, or (4) the force of static friction acting on A due to the top surface of B (b) Determine the forces of static friction on each block.