We must have noticed rails are not laid as a single continuous piece. Instead they are joined at regular intervals.
This is because manufacturing and transporting a single raip for thousands of kilometers is neither practical nor feasible.
Therefore multiple rail sections are connected to form a continuous track.
But there is a small gap between two joined rails. It is carefully engineered safety measure.
Railway tracks are made of iron and steel. Metals naturally expand in hot weather and get contract in cold weather.
If no space is left between two rail sections, the expansion in higher temperature could cause the tracts to bend or buckle.
It is a dangerous condition that result in derailment.
The gap provided allows the metal to expand safely without distorting the alignment of tracks.
Other safety measure is trains halting at the outer signal before entering the station.
Because signalling and track clearance play a crucial role in such stops.
