MFRI Rescue Technician Vehicle and Machinery Extrication (VME) Practice Test

The catenary wire system primarily provides electrical power to trains. This system consists of overhead wires that deliver electricity directly to the train through a pantograph, which is a device mounted on top of the train. When the pantograph makes contact with the overhead wires, it draws electrical power, enabling electric trains to operate efficiently and maintain high speeds.

Electric train systems benefit from the catenary wire setup, as it allows for continuous power supply over long distances without the need for heavy batteries. This contributes to improved performance, reduced weight, and enhanced efficiency compared to other forms of power delivery, such as diesel engines. The use of catenary systems is particularly prevalent in urban transit systems, intercity rail networks, and light rail systems where electric traction is preferred for sustainability and pollution reduction.

Other choices like communication signals, water supply, and control of train speed are unrelated to the function of catenary wires. Communication signals can be provided through separate infrastructure and do not rely on the electrical overhead lines. Water supply is not applicable to train propulsion and is more relevant in contexts such as steam trains or for passenger services. Control of train speed involves different systems, often related to signaling and braking mechanisms, rather than the power supply provided by a caten