How are higher pairs characterized in terms of element contact_________________?
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Answer: A. point or line contact between the two elements when in motion
Explanation
Higher pairs feature point or line contact to transmit forces between mating kinematic elements. This specific contact geometry distinguishes higher pairs from mechanisms sharing broad surface areas. The concentrated contact stress requires careful material selection to prevent premature surface fatigue. Kinematic pairs are classified based on the nature of contact between their constituent moving elements. Surface contact defines lower pairs, whereas point or line contact characterizes higher pair connections. Cams, gears, and ball bearings are classic engineering examples of higher pair mechanical connections.
Gear teeth mesh along instantaneous contact lines to transmit rotational power efficiently in gearboxes. Rolling element bearings utilize spherical or cylindrical elements to minimize friction via point contact. Engineers analyze contact stresses to ensure mechanical components withstand high operational loads safely. Option B describes surface contact which is characteristic of lower pairs rather than higher pairs. Option C refers to unconstrained assemblies rather than properly defined kinematic pairs in mechanisms. Option D provides a general definition of kinematic pairs without specifying contact characteristics.
- Subject
- Engineering
- Category
- Mechanical Engineering
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- —
- Difficulty
- medium
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