नहीं कोई गम, रेलवे से हैं हम - Aman

Messes of Track's...!

kindly chk the link for details.
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If you see the wheel of any engine/bogie, (tech name I do not konw), it sits on the track but inside there is a big grip like finishing, which holds the wheel on the track. The exterior sided is plain. There is no steering wheel like motor vehicles - cars, buses etc. The track alignment guides the engine and the compartments. Whenever the points are set for the train to move from one track to the other, as you can see in the photo in the entry, they are open ended. The train just moves over comfortably. Depending upon the angle of the points and curvature, speed restrictions will be placed. That is why, trains slow down when moving from main to loop or vice versa.
Vasan

when u observe the wheel u can see the inner portion is a little bit down than the outer one.. that means the inner acts as a giude... now see the pic... the wheel is there and the track is set to go straight... so what happens is tat since the track is open, it can go straight..
Now when the track is switched, the open portion joins the track and the closed one in the figure opens up... So wat hapens as the diameter of the inner is greater than the outer, as the wheel reaches the switch, the wheel travels throu the switch to the new one

for the animation see this link... Source of Animation.. Wiki
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