Final answer:
Train speeds are authorized by the Operating Rules, Special Instructions, and railroad regulations to ensure safe and efficient train operations.
Step-by-step explanation:
In the context of train speeds, the authorized speeds are determined by various factors including the Operating Rules, Special Instructions, and railroad regulations.
These regulations ensure the safety and efficiency of train operations. They may specify maximum speeds for different track sections, train types, and various operational conditions. For example, in some areas, there may be speed restrictions due to curves, hills, or potential hazards.
Additionally, the authorized speeds may also take into account factors like train weight, braking capabilities, and the need to maintain a safe distance between trains. These rules and instructions are designed to prevent accidents, derailments, and other incidents that could occur if trains were allowed to operate at unrestricted speeds.
It's important to note that the authorized train speeds may vary depending on the country, railway company, and local regulations. Therefore, it is crucial for train operators to be aware of and follow these rules to ensure safe and efficient train operations.