What is a kinematic pair called whose elements are held in contact by mechanical constraints ___________________?
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Answer: A. closed pair
Explanation
A closed pair maintains physical contact between elements through mechanical constraints built into their geometry. The physical design of the mating surfaces prevents any separation during normal machine operation. This specific mechanical constraint ensures predictable relative motion without relying on external forces. Kinematic pairs are fundamental building blocks used by mechanical engineers to construct complex mechanisms. Lower pairs feature surface contact, whereas higher pairs involve point or line contact during motion. Closed pairs are commonly contrasted with unclosed pairs which require external forces like springs or gravity.
Piston and cylinder assemblies rely on closed pairs to maintain reliable sealing and precise guidance. Machine tools utilize these mechanical constraints to ensure high precision during repetitive manufacturing tasks. Properly constrained linkages prevent unexpected jamming or structural failure in industrial automation equipment. Option B describes an open pair where elements are not mechanically locked together by design. Option C is a generic term that does not accurately classify this specific kinematic pairing type. Option D refers to rolling contact pairs rather than mechanically constrained sliding kinematic pairs.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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