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प्रश्न
Answer the following question.
Give an example of the disadvantages of thermal stress in practical use?
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उत्तर
Disadvantage: Thermal stress can lead to fracture or deformation in substance under certain conditions.
Example: Railway tracks are made up of metals which expand upon heating. If no gap is kept between tracks, in hot weather, the expansion of metal tracks may exert thermal stress on track. This may lead to bending of tracks which would be dangerous. Hence, railway track is not a continuous piece but is made up of segments separated by gaps.
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