Problem 16.11

16.11
We know that at $-35{}^{\circ}C$, the wire is 35 m long.
The equation for length change is
$\Delta L = L_{0} \alpha \Delta T$
For copper at $-20{}^{\circ}C$,
$\alpha = 1.7 \times 10^{-5} deg^{-1}$
$\Delta L = (35 m)(1.7 \times 10^{-5} deg^{-1})(55{}^{\circ}C)$
$\Delta L = 3.27 cm$