Question

100 cm of brass increased by 0.18 cm when its temperature rises by 95°C. What is the linear expansivity of brass?

Answer 1

Given:

$l_0=100\:\rm cm$

$\Delta l=0.18\:\rm cm$

$\Delta t=95\:\rm K$

The thermal expansion is described by an equation

$$\Delta l=l_0\alpha\Delta t$$

Hence, the linear expansivity

$$\alpha=\Delta l/(l_0\Delta t)$$ $$\alpha=\rm 0.18\: cm/(100\: cm*95 \: K)=1.9*10^{-5}\: K^{-1}$$