The bend part of a metal frame, of same cross-sectional area carries heat current of 60W . Total heat current from hotter to colder end is

Let ${\mathrm{i}}_1$ and ${\mathrm{i}}_2$ are the heat current through bend and straight segment, so

$\frac{{\mathrm{i}}_2}{{\mathrm{i}}_1}=\frac{{\mathrm{R}}_1}{{\mathrm{R}}_2}=\frac{{\mathrm{l}}_1}{{\mathrm{l}}_2}=\frac{60}{50}$

$$\begin{gathered} \Rightarrow {\mathrm{i}}_2=\frac{6}{5}{\mathrm{i}}_1=\frac{6}{5}\times 60=72 \mathrm{W} \\ \Rightarrow \mathrm{Total} \mathrm{heat} \mathrm{current} {\mathrm{i}}_1+{\mathrm{i}}_2=60+72=132 \mathrm{W} \end{gathered}$$