Write brief answers.

Explain why rails have gaps at specific distances.

Temperature is an important parameter in deciding the size and shape of solids especially metals. Rails are made up of steel. As temperature increases, metals will undergo expansion and it contracts on the decrease in temperature. Since due to high temperature, rails will expand on the summer season and will undergo contraction in winter season due to a lower temperature.

This continues contraction and expansion may cause sagging or bending in rails. So in order to avoid the damages due to this contraction and expansion, some gaps are made at specific distances on the rail. So in the summer season, even metal expands, will not cause wear and tear on rails. In winter, these gaps will be wider. Thus, the gaps on rails protect it from damages due to temperature changes.