Question
Two slabs A and B of thermal conductivity Kl and K2, length l2 and l2 and each of cross section area A are placed in scries. The free end of slab A is at temperature T1 and that of slab B is T2 <T1. Find the temperature at the interface of two slabs. Also find the rate of flow of heat through compound slab in steady state.
Solution
Let T be the temperature at the interface of two slabs
The rate of flow of heat through slab A is,
The rate of flow of heat through slab B is,
As two slabs are in series, therefore the rate of flow of heat through them will be same.
The rate of flow of heat through composite slab is,