In the following figure, two insulating sheets with thermal resistances R and 3R as shown in figure. The temperature θ is
The temperature $ \mathrm{\theta }$ at the junction of two insulating sheets, having thermal resistances $ {\mathrm{R}}_{1} \mathrm{and} {\mathrm{R}}_{2}$ as well as the bottom and top temperatures $ {\mathrm{\theta }}_{1} \mathrm{and} {\mathrm{\theta }}_{2}$ (as shown in the figure) is given by: