Final answer:
The phrase 'has authority and control of main line and other controlled track' pertains to railway operations and the control systems that regulate train movements, including the use of electromagnetic waves emitted by power lines for communication and signaling purposes.
Step-by-step explanation:
The question refers to the authority and control of main line and other controlled track, which typically relates to railway operations and the systems in place to manage and control train movement. In this context, it's likely touching on the physics of how electromagnetic waves, emitted by high-voltage traction power lines, might influence or be part of the control systems. High-voltage lines, like the one running to the Eutingen Railway Substation in Germany, radiate electromagnetic waves with very long wavelengths. These waves can be integral to communication and signaling systems that are fundamental for the safe and efficient operation of railway networks.
Railway systems rely on a complex interplay of mechanical and electrical systems to ensure that trains can travel safely. This includes the electrical power supplied to the trains and the control systems that regulate train schedules, track changes, and signal operations. The experience of the regular commuters, instinctively knowing the status of a train's punctuality, reflects the importance of these control systems in maintaining a predictable and reliable train service.