What characteristic defines the two elements forming a kinematic pair______________?
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Answer: C. permit relative motion
Explanation
The fundamental definition of a kinematic pair requires that its two constituent elements have constrained relative motion. Without relative motion between the connected parts, the assembly cannot function as a working mechanism. This relative movement distinguishes mechanical linkages from rigid, stationary structural assemblies. Franz Reuleaux formulated the foundational theories of kinematics, defining links, pairs, and kinematic chains. Kinematic pairs are categorized by their type of contact and the degrees of freedom of relative motion permitted. Standard classifications group these pairs into lower pairs and higher pairs based on surface versus point contact.
Line contact describes specific higher pairs like gears or cams but does not apply universally to all pairs. Surface contact characterizes lower pairs but excludes higher pairs which rely on point or line contact. Holding elements together describes closed pairs rather than the universal kinematic requirement of relative motion.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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