Answer:
The temperature difference across the stainless steel is 18°C
Explanation:
The heat flows through the plastic layer by convection and then through the steel layer by conduction and then through the plastic layer on the other side.
The heat flux q/A can be expressed as:
[tex]q/A = h*\Delta T[/tex]
It can also be expressed as
[tex]q/A=h*(T_A-T_B) = h_1(T_A-T_1)=k/\Delta x*(T_1-T_2)=h_2(T_2-T_B)[/tex]
being Δx/k*(T1-T2) the conductive heat flux through the steel.
If we want to know the temperatur difference across the stainless steel (T1-T2) we can write:
[tex](k/\Delta x)*(T_1-T_2)=h*(T_A-T_B)\\\\(T_1-T_2)=(\Delta x/k)*h*(T_A-T_B)\\\\(T_1-T_2)=(0.04/16)*120*60=18 \, ^{\circ} C[/tex]
