Question

The outer face of a rectangular slab of equal thickness of iron and brass are maintained at `100^(@)C` and `0^(@)C`, respectively. Find the temperature of the interface. The conductivities of iron and brass are 14 and `126 Wm^(-1) K^(-1)` respectively.

Answer 1

Correct Answer - `[10^(@)C]`
If T is temperature of the interface of iron and brass slabs, then
`(dQ)/(dt)=K_(1)(A(100-T))/(Delta x) =(K_(B)A(T-0))/(Delta x)`
or `K_(1)(100-T)=K_(B)T`
or `(100-T)/(T)=(K_(B))/(K_(1))=(126)/(14)=9` or `T=10^(@)C`