Physics - Heat & Thermo Question with Solution | TestHub

A brass bar and a steel bar are each $0.800\mathrm{m}$ long at $20^{\circ }\mathrm{C}$. Each is placed at that temperature between rigid walls $0.800\mathrm{m}$ apart. Their cross-sectional areas are $0.005{\mathrm{m}}^2$ and $0.003{\mathrm{m}}^2$, respectively. Thermal and elastic constants are given below. The temperature is raised until the combined force exerted by the bars is $1.8\times 10^6\mathrm{N}$. The temperature, in degrees Celsius, is closest to:

Brass: $\alpha =2.0\times 10^{-5}{\mathrm{K}}^{-1}$, $Y=0.9\times 10^{11}\mathrm{Pa}$.

Steel: $\alpha =1.2\times 10^{-5}{\mathrm{K}}^{-1}$, $Y=2.0\times 10^{11}\mathrm{Pa}$.