Thermal expansion (surface area)

[jisbon]

Homework Statement

Consider an empty and closed box made of isotropic material. The surface
area of the box is $52 cm^2$ at 25 °C. The linear coefficient of thermal expansion
of the material is $24*10^{-6}$K. If the temperature of the box is raised to 125 °C,
calculate
(i) its surface area and
(ii) the percentage increase of the volume using the percentage increase of
the surface area.

Relevant Equations

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Hi all,

For area expansion, I know the equation goes like:

Hence, my answer to part i is
$\begin{aligned}A=A_{0}\left( 1+2\alpha \Delta T\right) \\ = 52\left( 1+2*24\times 10^{-6}\right) \left( 100\right) \\ =52.2496cm^{2}\end{aligned}$

Now I am unsure how to proceed with part 2 in this case, any pointers?

Thanks

 

[mitochan]

You shall find the relation between
$$(V-V_0)/V_0$$ and $$(A-A_0)/A_0$$ with the further formula $$V=V_0(1+3\alpha\triangle T)$$