What mechanical effect occurs if a structural component is allowed to expand freely due to temperature increase ____________________?
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Answer: E. no stress
Explanation
If a structural component is allowed to expand freely without constraints when heated, no thermal stresses are induced. Thermal stresses only develop when dimensional changes due to temperature variations are physically prevented by boundary supports. Unrestricted thermal expansion allows internal atoms to move apart freely without generating opposing internal reaction forces. Materials expand when heated and contract when cooled according to their specific linear coefficient of thermal expansion. Thermal strain is calculated directly as the product of the expansion coefficient and the temperature change experienced. Hookes law dictates that stress is proportional to strain only when physical boundaries prevent free movement.
Thermal stresses cannot occur when components are completely free to expand without any external mechanical constraints opposing them. Tensile stress only develops during thermal cooling when contraction is physically restricted by rigid end supports. Bending stresses require eccentric loading or transverse temperature gradients rather than uniform unconstrained thermal expansion.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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