Question

Six identical metallic rods are joined together in a pattern as shown in the figure. Points $A$ and $D$ are maintained at temperatures $60^{\circ }C$ and $240^{\circ }C$. The temperature of the junction $B$ will be

• A. $120^{\circ }C$
• B. $150^{\circ }C$
• C. $60^{\circ }C$
• D. $80^{\circ }C$

Answer 1

Answer: (A)

Equivalent eiectrical circuit will be as shown in the figure
Temperature difference between $A$ and $D$ is $180^{\circ }C$,
which is equally distributed in all the rods.
Therefore, temperature different between $C$ and $D$ will be $60^{\circ }C$ or temperature of $C$ should be $=180^{\circ }$
So, the temperature at junction $B$
$180^{\circ }-\theta =\theta -60^{\circ }$
$\theta =120^{\circ }C$