Determine the heat transfer rate across a composite slab which is made of different materials with top and bottom as shown in fig. 3.16. The entire left-hand face is held at the temperature T1 while the entire right hand face is at the temperature T2. The conductivities of the two different materials are stated as ka and kb, and their areas as viewed in the direction of slab thickness δ are Aa and Ab respectively. Steady state exists, there is no heat generation and the slab is so thin that any edge effects can be neglected. Interpret the result in terms of an electrical circuit.
