Question

Older railroad tracks in the U.S. are made of 12 m-long pieces of steel. When the tracks are laid, gaps are left between the sections to prevent buckling when the steel thermally expands. If a track is laid at 16 ?C, how large should the gaps be if the track is not to buckle when the temperature is as high as 50 ?C?

Answer 1

Answer:

0.005 m

Explanation:

length of steel (L°) = 12 m

initial temperature (T) = 16 degrees

expected temperature (T') = 50 degrees

We can find how large the gaps should be if the track is not to buckle when the temperature is as high as 50 degrees from the formula below

ΔL = ∝L°ΔT where

• ΔL = expansion / gap
• ∝ = linear expansion coefficient of steel = $12x10^{-6} C^{-1}$
• L° = initial length
• ΔT = change in temperature

ΔL = $12x10^{-6}$ x 12 x (50-16) = 0.005 m