Physics - Heat & Thermo Question with Solution | TestHub

A composite bar of length $\mathrm{L}={\mathrm{L}}_1+{\mathrm{L}}_2$ is made up from a rod of material 1 and of length ${\mathrm{L}}_1$ attached to a rod of material 2 and of length ${\mathrm{L}}_2$ as shown. If ${\alpha }_1$ and ${\alpha }_2$ are their respective coefficients of linear expansion, then equivalent coefficient of linear expansion for the composite rod is: