Three rods made of same material and having same cross section has been joined as shown in the figur

Question

Three rods made of same material and having same cross section has been joined as shown in the figure. Each rod is of the length. The temperature at the junction of the three rods is\

Professor PC Thomas Classes · Answer

BC and BD are in parallel. The thermal resistance for the combination is half that of AB . Therefore the thermal conductivity is double that of $\mathrm{AB}, \mathrm{V}=$ potential-Temperature\ $\frac{\mathrm{V}}{\mathrm{R}}=\frac{\mathrm{KA}(\mathrm{T}-0)}{\mathrm{L}}=\frac{2 \mathrm{KA}(90-\mathrm{T})}{\mathrm{L}}$\ $\mathrm{T}=180-2 \mathrm{~T} \Rightarrow \mathrm{~T}=60^{\circ} \mathrm{C}$\