Which of the following mechanism connections qualifies as a lower pair_______________?
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Answer: D. A. and B. above
Explanation
Ball and socket joints maintain spherical surface contact while piston-cylinder assemblies use cylindrical surface contact. Both connection types rely on broad surface contact areas to transmit loads between moving components. Surface contact is the defining mechanical feature that classifies both connections as lower pairs. Lower pairs provide surface contact between mating elements to constrain relative motion securely. Spherical lower pairs permit rotational motion in multiple planes around a fixed center point. Translational lower pairs like pistons guide linear reciprocating movement with high load capacity.
Suspension linkages utilize ball and socket joints to handle multi-directional steering and load forces. Reciprocating compressors rely on piston and cylinder assemblies to compress gases using surface contact. Engineering designs prioritize lower pairs for high-load applications due to their excellent load distribution. Option C features cam and follower mechanisms which involve point or line contact higher pairs. Option E uses flexible belts which transmit power via tension rather than rigid lower pair contact. Selecting options individually fails because both listed choices correctly qualify as lower pairs.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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