Question

A medallion made of nickel (coefficient of linear expansion = 1.5 x 10^-5/K) has a diameter of 0.1m at 20^oC. What will be its diameter at 35^oC?

Answer 1

Linear expansivity$(\alpha)={l_2 - l_1 \over l_1(\theta_2 -\theta_1)}$

$\alpha=1.5×10^{-5}$

$l_1=0.1m$

$l_2=?$

$\theta_1=20°C=293K$

$\theta_2=35°C=308K$

$l_2= \alpha l_1(\theta_2 - \theta_1)+l_1$

$l_2=1.5×10^{-5}×0.1(308-293)+0.1$

$l_2=0.1000225m$