How can the elastic stress-strain response of rubber be described_____________________?
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Answer: B. non-linear
Explanation
Rubber exhibits a stress-strain response that deviates significantly from a straight line. Large elastic deformations occur under relatively small tensile loads during stretching. This unique mechanical behavior stems from the coiled polymer chain structure of elastomers. Elastomers stretch extensively and snap back to their original shape when released. Hookes law of linear elasticity does not apply to materials undergoing rubber-like elasticity. Entropy changes within polymer chains drive the elastic retraction forces observed in rubber.
Rubber seals, tires, and mounts rely on this non-linear elasticity to absorb shocks. Engineers must use specialized constitutive equations to model elastomeric components accurately. Understanding non-linear stress response prevents failure in vibration isolation systems. Linear stress-strain behavior follows Hookes law, typical of metals within elastic limits. Plastic behavior implies permanent deformation without elastic recovery upon load removal. Unpredictable behavior is avoided through rigorous material testing and standards compliance.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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