What makes metro train run?

Question

What makes metro train run?

Answer 1

electricity runs trhough da rails

Answer 2

Unless I'm mistaken the Metro trains run above ground and if they do, they are supplied electricity from overhead wires via a cantenery system that connects to the locomotive, and maintains contact with the overhead as the train moves along the tracks.

I'm sure someone else will be answering with the voltages used, but I'm going to make a guess at somewhere around 880 volts.  This is a wild guess and I'm looking forward to being informed if I'm incorrect.

Answer 3

electricity..

Answer 4

Electric power.  There are two systems for current collection:

Third rail, commonly used in all metro systems in USA.  It consists of a rail that carry the electric power and trains pick up it with shoes at side of the wheelsets.   The power can vary from 600 V to 800 V DC.

Catenary, not common in older systems or in USA, but there are several metros in the world that uses overhead wire.  Trains pick up current by means of "pantographs", articulated arms with a shoe on top that press on the wire.  Current goes from 600 V to 3000 V.  Normally AC current supply is not used on the metro systems but yes on the suburban/commuter train systems.