Most railroad tracks are built from pieces of steel supported by wooden ties, and laid with a gap between the ends. Why are these gaps provided in railway tracks?

Explanation:

The reasons are:

Firstly , the thermal expansion of solid at higher temperatures.

During the summer season, the steel tracks may expand due to thermal expansion and if gaps are not laid the tracks will bend and lead to accidents.

Secondly, imbibition of water during rainy season.

During the rainy season the wooden tracks will imbibe water and swell. If gaps are not provided, this may result irregular levels of railway track. This may prove very dangerous and lead to railway accident.

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