Question
An iron bar $\left(L_1=0.1 m , A_1=\right. \left.0.02 m ^2, K_1=79 W m ^{-1} K ^{-1}\right)$ and a brass bar $\left(L_2=0.1 m , A_2=0.02 m ^2\right.$, $K_2=109 W m ^{-1} K ^{-1}$ ) are soldered end to end as shown in Fig. $10.16.$ The free ends of the iron bar and brass bar are maintained at $373 K$ and $273 K$ respectively. Obtain expressions for and hence compute $(i)$ the temperature of the junction of the two bars, $(ii)$ the equivalent thermal conductivity of the compound bar, and $(iii)$ the heat current through the compound bar.
