What is the definition of an MU car?

An MU car refers to a type of passenger car that is designed to operate in multiple units. This term stands for "multiple unit," indicating that these cars can be coupled together and controlled from a single operator's cab. In practice, this allows for greater efficiency and flexibility in train operations, as multiple MU cars can be handled together without needing a separate locomotive for each car.

MU cars are commonly used in commuter rail and subway systems, enabling smooth and quick adjustments to train configurations based on demand. The ability to control multiple cars from one point provides improved acceleration and braking dynamics and enhances the overall passenger experience.

In contrast, the other options refer to specific types of rail vehicles that do not fall under the definition of MU cars. Freight transport cars, light engines for shunting, and specialized maintenance cars serve distinct purposes and cannot perform the functions associated with multiple unit operations.