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प्रश्न
Why are gaps left between successive rails on a railway track ?
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उत्तर
The rails of railway track are made of steel. While laying the railway track, a small gap is left between the two successive length of rails. The reason is that the rails expand in summer. The gap is provided to allow for this expansion. If no gap is left, the expansion in summer will cause the rails to bend sideways. This may result in a train accidents.
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संबंधित प्रश्न
Fill in the blank
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| 1. | Solid to liquid | a. | Condensation |
| 2. | Liquid to gas | b. | Deposition |
| 3. | Gas to solid | c. | Melting |
| 4. | Gas to liquid | d. | Vaporization |
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