Question

why do the pillars holding the track of Metro trains have a broader bass

Answer 1

the are boader to increase the surface area so that the pressure is reduced .

since pressure and surface area is inversely proportional .

Answer 2

Hello dear 
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Metro runs a broader base because F    = ma 
force is directly proportional to mass and acceleration of the object 
if mass is increased then force will increased and when acceleration will increase then force will also increase
and force directly proportional to pressure  P = F/A
after all large mass and great speed leads to high pressure create so we
need great support to spot the metro they cant be fall or minimizing the accidents
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