Question by Ryan C: Why DC voltage is utilized in locomotive or in Electric trains?
Answer by morningstar
DC current is constant, AC current varies in voltage during its cycle. If an electric motor, such as those found in trains, is under AC, the motor would probably either speed up then slow down and then speed up and slow down, etc. Or go forward, reverse, forward, reverse, etc. in a quick fashion. DC current being constant, makes the motor run at a constant speed and direction since the electrical flow is constant. I think that makes sense, and that’s how I understand it.
Add your own answer in the comments!