## Physics (10th Edition)

$5.0\times10^{-3}\,(C^{\circ})^{-1}$
$R=R_{0}(1+\alpha\Delta T)$ where $\alpha$ is the temperature coefficient of resistivity. $\implies \alpha=\frac{R-R_{0}}{R_{0}\Delta T}=\frac{43.7\,\Omega-38.0\,\Omega}{38.0\,\Omega\times(55-25)^{\circ}C}=5.0\times10^{-3}\,(C^{\circ})^{-1}$