Solution to Problem 261 Thermal Stress

$\delta = \delta_T + \delta_{st}$

$\dfrac{\sigma \, L}{E} = \alpha \, L \, (\Delta T) + \dfrac{PL}{AE}$

$\sigma = \alpha \, E \, (\Delta T) + \dfrac{P}{A}$

$\sigma = (6.5 \times 10^{-6})(29 \times 10^6)(70) + \dfrac{1200}{0.25}$

$\sigma = 17\,995 \, \text{psi} = 18 \, \text{ ksi}$           answer

$\delta_T = \delta_{st}$

$\alpha \, L \, (\Delta T) = \dfrac{PL}{AE}$

$\alpha \, (\Delta T) = \dfrac{P}{AE}$

$(6.5 \times 10^{-6})(T - 70) = \dfrac{1200}{0.25(29 \times 10^6)}$

$T = 95.46 \, ^\circ\text{F}$           answer