$1$st step

: $=$ All steps

Step $1$

To find:

Determine the normal stress in the rails assuming that

the rails

$($a$)$ are welded to form a continuous track

$($b$)$ are $39$ ft long with $(1)/(4)$ in gaps between them.

Given data:

The initial temperature of the steel railroad track is

T$\_($i$)=30\backslash$deg F

The maximum temperature the railroad tracks reach is

T$\_($f$)=150\backslash$deg F

The Young's modulus of the steel is E$\_($S$)=29\backslash$times $10^(6)\backslash$psi

The thermal conductivity of the material is

$\backslash$alpha $\_($s $)=6\mathrm{.}5\backslash$times $(10^(-6))/(\backslash$deg $)$F

The length of the rails is l$=39$ft

The length of the Gap is $\backslash$delta l$=(1)/(4)$ in

Explanation:

Thermal stresses are the internal forces that

In this question $\backslash$alpha given as centigrade but change occered in feranhait scale, My question is that when we change $1$ centigrade change there will be $1\mathrm{.}18$ F change so this solution would wrong. If change occurred in kelvin then it must right because $1$ centigrade change equal to $1$ K change this my question if point is valid then give me right solution. If invalid then give me reason for it's invalidation