Answer to Question #299569 in Physics for Totti

Question

Calculate the change in temperature of an 900mm aluminium bar, that has increased in length to 901.035mm.

 α = 25 x 10^-6k^-1

Answer 1

Given:

$l_0=900\:\rm mm$

$\alpha=25*10^{-6}\:\rm K^{-1}$

$l=901.035\:\rm mm$

The thermal expansion is described by an equation

$$\Delta l=l_0\alpha\Delta t$$ $$\Delta t=\frac{\Delta l}{\alpha l_0}\\ =\rm \frac{901.035-900}{25*10^{-6}*900}=46\:{^\circ C}$$