Which of the following is an example of a spherical pair_____________________?
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Answer: C. ball and socket joint
Explanation
A ball and socket joint permits rotation in all directions, representing a spherical pair. The mating elements feature spherical surfaces that slide freely against each other. This geometry allows three degrees of rotational freedom around a single fixed center point. Spherical pairs are classified as lower pairs because they maintain surface area contact. Human shoulder joints act as biological equivalents of mechanical ball and socket joints. They accommodate complex multi-axial angular movements without binding.
Automotive suspension control arms and linkage joints frequently use ball and socket designs. Robotic arms incorporate spherical wrist joints to achieve versatile end-effector orientations. Mechanical designers select spherical pairs when multi-directional rotational freedom is required. Option A describes bolt and nut connections, which form screw pairs rather than spherical pairs. Option B names lathe lead screws that also utilize helical screw pair mechanics. Option D refers to rolling element bearings designed to support rotating shafts with line contact.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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