power car

A power car is a railroad vehicle that is closely related to the locomotive. What differentiates the two is their construction or their use. A true locomotive can be physically separated from its train and does nothing but provide propulsion (and electricity for passenger trains). A power car, on the other hand, is frequently an integral part of its train. Some of its interior space may be used for holding passengers or cargo. Power cars are limited to passenger trains as their relative lack of versatility makes them unsuitable for hauling freight.
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