I heard about train lines Broad , Meter gaze, Now on what sort of the line underground electric trains move?

Question

I heard about train lines Broad , Meter gaze, Now on what sort of the line underground electric trains move?

Answer 1

Gauge, not gaze, is the width between the individual lines of metal forming the parallel track. Undergound electric trains use exactly the same system of metal wheels on metal rail (except in Paris where some have pneumatic tyres). Gauge is normally the standard of 4' 81/2'', (any greater width being 'broad gauge'), except in countries (Russia and Ireland, for example) where a broader gauge is normal. Some underground systems run on a narrower gauge which might or might not be metre gauge. For example, the Glasgow Subway has the unusal gauge of 4'0''