To solve this problem we will use the concepts related to thermal expansion in a body for which the initial length, the coefficient of thermal expansion and the temperature change are related:
[tex]\Delta L = L0\alpha\Delta T[/tex]
Where,
[tex]\Delta L[/tex] = Change in Length
[tex]\alpha[/tex] = Coefficient of linear expansion
[tex]\Delta T[/tex] = Change in temperature
[tex]L_0[/tex] = Initial Length
Our values are:
[tex]L_0 = 3.45m[/tex]
[tex]\alpha = 5.5*10^{-7} \°C^{-1}[/tex]
[tex]\Delta T = 235-20 = 215\°C[/tex]
Replacing we have,
[tex]\Delta L = (3.49) (5.5*10^{-7}) [(215)[/tex]
[tex]\Delta L = 0.0004126m[/tex]
[tex]\Delta L = 0.4126mm[/tex]
Therefore the change in milimiters was 0.4126mm
