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प्रश्न
Explain why rails have gaps at specific distances.
उत्तर
All solids expand on heating. As rails are made up of steel, these also expand in summers and contract in winters. This expansion and contraction can cause sagging and bending of rails which could derail the trains running on them. Thus, the rails have been provided with gaps at a specific distance so as to prevent this bending of rails. These spaces get closer in summers and wider in winters.
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