Thermal Conduction - Finding Temperature of Interface Between 2 Slabs

[MadmanMurray]

Homework Statement

Two well-insulated slabs, one of steel the other of copper, are in close contact as illustrated.

Find the temperature at the interface between the two slabs & also the rate at which heat is transferred across the slabs.

Thermal conductivities of steel and copper are 50WmK and 385WmK

Left side of steel slab has an area of 90cm² and temperature of 427C. The steel slab has a length of 20cm.

Right side of copper slab has area of 90cm² and temperature of 77C. Length of slab is 30cm

Homework Equations

The Attempt at a Solution

I'm completely stuck. I know a formula to find the rate of heat transfer through the slabs but I don't have a clue how to find the temperature at the interface of these 2 slabs.

 

[mgb_phys]

Just think of them as resistors in series = a potential divider.