Two metal rods 1 and 2 of same lengths have same temperature difference between their ends. Their thermal conductivities are K_1 and K_2 and cross…

Two metal rods $\displaystyle 1$ and $\displaystyle 2$ of same lengths have same temperature difference between their ends. Their thermal conductivities are $\displaystyle \mathrm{K}_1$ and $\displaystyle \mathrm{K}_2$ and cross sectional areas $\displaystyle \mathrm{A}_1$ and $\displaystyle \mathrm{A}_2$, respectively. If the rate of heat conduction in $\displaystyle 1$ is four times that in $\displaystyle 2$, then :