sheet of rubber and a sheet of cardboard each 2 mm thick are pressed together and their outer faces are maintained respectivély at 0°C and 30°C. If the thermal conductivities of rubber and cardboard 10. are respectively 0.13 and 0.05 w/m/k, find the quantity of heat which flows in one hour across a piece of the composite sheet of area 100 cm. Steam at 100° [T.U. 2050] 11.
