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

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

Solution:

Let the temperature of junction be $ theta , $

then $ H={{H}_{1}}+{{H}_{2}} $

$ Rightarrow $ $ frac{KA(theta -0)}{L}=frac{KA(90-theta )}{L}+frac{KA(90-theta )}{L} $

or $ theta =90-theta +90-theta $

or $ theta =180-26 $

or $ 3theta =180 $

or $ theta =60{}^circ C $