What type of relative motion occurs in a higher kinematic pair_____________________?
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Answer: E. combination of sliding and turning
Explanation
Higher kinematic pairs have point or line contact between the mating surfaces. Under mechanical loads, this concentrated contact geometry causes simultaneous sliding and turning. Cam and follower or gear tooth interactions are classic examples of this combined motion. Lower pairs feature area contact while higher pairs feature point or line contact. Kinematic classification distinguishes between surface-contact hinges and point-contact cams. Friction and wear are generally higher in higher pairs due to concentrated contact stresses.
Gear teeth mesh with a combination of rolling and sliding relative motion across profiles. Cam mechanisms rely on higher pair contact to achieve complex follower displacement paths. Lubrication engineers must protect higher pair contacts from scuffing and pitting failures. Purely turning motion is characteristic of lower pairs like hinge pins and shaft bearings. Purely sliding motion occurs in prismatic joints like cross-heads and piston guides. Pure surface contact describes lower pairs rather than point or line contact higher pairs.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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