Does a chain consisting of 5 links and 5 joints constitute a valid kinematic chain ?
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Answer: B. no
Explanation
According to Grubler's criterion for planar mechanisms, a chain with 5 links and 5 joints lacks constrained mobility. Calculating degrees of freedom using the standard kinematic formula yields a structure that cannot move predictably. A valid constrained kinematic chain requires a specific mathematical relationship between its number of links and joints. Kinematic chains are assemblies of interlinked rigid bodies designed to transmit motion and mechanical forces. Grubler's criterion equates degrees of freedom to three times the number of links minus two times lower pairs. Structures with degrees of freedom greater than zero require proper anchoring to form functional machinery.
Mechanical engineers apply Grubler's criterion during the conceptual design phase of linkages and mechanisms. Building invalid kinematic chains results in jammed mechanisms or uncontrolled structural deformations. Understanding link-joint mathematics prevents costly prototype redesign errors in industrial machine design. Option A is incorrect because five links and five joints fail the mathematical criteria for a constrained chain. Option C describes a marginal case, but mathematical formulas yield a definitive structural failure. Option D is wrong because sufficient data regarding links and joints is provided to evaluate mobility.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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