# Relationship between thermal conductivity and reaching the steady temperature?

The diagram is for three materials with different thermal conductivities. I think number 1 is the material with higher thermal conductivity because it transfers the heat faster so it gets to the steady temperature sooner than the other two. Am I right? If not or if my reasoning isn't correct, I appreciate your help.

$\dot{Q} = k A \frac{\Delta T}{l}$
$l$ thickness
$A$ surface area
From this follows that besides other factors the rate of heatflow is proportional to the thermal conductivity $k$.
$\dot{Q} \propto k$