Explain in terms of kinetic molecular theory the need for gaps in railway lines
According to the kinetic molecular theory, particles in a substance are constantly in motion and possess kinetic energy. In the case of a railway line, gaps are necessary between sections of the track to allow for expansion and contraction of the metal due to changes in temperature.
When the metal rail tracks are exposed to changes in temperature, they expand or contract. If the railway lines were continuous without any gaps, the expanding or contracting metal would cause the tracks to buckle or bend, leading to potential accidents and disruptions in train services.
By having gaps in the railway lines, the metal tracks are able to expand or contract freely without causing any structural damage. This allows for a smoother and safer operation of trains, as it prevents any potential hazards that could arise from thermal expansion or contraction of the metal tracks.