Question

A metal rod of length $2m$ has cross sectional area $2A$ and as shown in figure$.$ The ends are maintained at temperature ${100}^{0}C$ and ${70}^{0}C$.$ The tem[temperature at middle point C is

• A. ${90}^{0}C$
• B. ${30}^{0}C$
• C. ${45}^{0}C$
• D. ${60}^{0}C$

Answer 1

The correct option is A ${90}^{0}C$

$\begin{array}{c}LetqbetemperatruremiddlepointCandinseriesrateofheatflowissame\\ K\left(2A\right)\left(100-\theta \right)=KA\left(\theta -70\right)\\ 200-2\theta =\theta -70\\ 3\theta =270\\ \theta ={90}^{0}C\end{array}$

Hence,

option $\left(A\right)$ is correct answer.