Why are there gaps at regular intervals between consecutive rails in a railway track? State the relation between linear expansion coefficient (α), superficial expansion coefficient (β) and volume expansion coefficient (γ). [2+1]
WBBSE
Class X
Physical Science
Thermal phenomena
03 Mark
2025
Gaps are left between railway rails to provide space for thermal expansion during hot weather. This prevents the rails from bending or buckling, thereby avoiding accidents.
The relation between the coefficients of expansion is:
α : β : γ= 1 : 2 : 3
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