For Exercises 1 through 5:
a. Draw an interaction diagram.
b. Identify the “system” on your interaction diagram.
c. Draw a free-body diagram for each object in the system. Use dashed lines to connect members of an action/reaction pair.

Block A in FIGURE EX7.4 is heavier than block B and is sliding down the incline. All surfaces have friction. The rope is massless, and the massless pulley turns on frictionless bearings. The rope and the pulley are among the interacting objects, but you’ll have to decide if they’re part of the system.

FIGURE EX7.4: