Five identical rods are joined as shown in figure. Point A and C are maintained at temperature 120^o

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10-2.Transmission of Heat

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Five identical rods are joined as shown in figure. Point $A$ and $C$ are maintained at temperature $120^o C$ and $20^o C$ respectively. The temperature of junction $B$ will be....... $^oC$

A

$100$

B

$80$

C

$70$

D

$0$

Solution

(c) If thermal resistance of each rod is considered $R$ then, the given combination can be redrawn as follows

(Heat current)$_{AC} =$ (Heat current)$_{AB}$

$\frac{{(120 – 20)}}{R} = \frac{{(120 – \theta )}}{R}$

==> $\theta = 70^\circ C$

Standard 11

Physics

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