1. The problem statement, all variables and given/known data The thermal conductivity of aluminum is twice that of brass. Two rods, one of aluminum and the other of brass, are joined together end to end in excellent thermal contact. They are of equal lengths and radii. The free end of the brass rod is maintained at 0°C while the free end of the aluminum rod is kept at 200°C. Under these conditions of steady heat flow, what is the temperature at the joint between the two rods? 2. Relevant equations Q/t = KA (T1-T2)/L 3. The attempt at a solution I was thinking I had to set the rate of heat flow in the brass and aluminum to be equal and then isolate to find T1, but that turned out to be way wrong. How should I start? I read a similar problem that said we should add the conductivities of the two metals. For example, conductivity of brass = x, conductivity of aluminum = 2x, therefore overall conductivity is 3x.