Concept explainers
For Exercises I 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.
1. A soccer ball and a bowling ball have a head-on collision at this instant. Rolling friction is negligible.
2. A weightlifter stands up at constant speed from a squatting position while holding a heavy barbell across his shoulders.
3. A steel cable with mass is lifting a girder. The girder is speeding up.
4. 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 and FIGURE EX7.5
5. Block A in FIGURE EX7.5 is sliding down the incline. The rope is massless, and the massless pulley turns on frictionless bearings, but the surface is not frictionless. The rope and the pulley are among the interacting objects, but you'll have to decide if they're part of the system.
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Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (4th Edition)
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