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Question
Answer the following question.
What is thermal stress?
Solution
- Consider a metallic rod of length l0 fixed between two rigid supports at T °C.
- If the temperature of rod is increased by ΔT, length of the rod would become, l = l0 (1 + αΔT) Where, α is the coefficient of linear expansion of the material of the rod.
- But the supports prevent the expansion of the rod. As a result, rod exerts stress on the supports. Such stress is termed as thermal stress.
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