The thermal conductivity of a sheet of rigid, extruded insulation is reported to be k = 0.029 W/m· K. The measured temperature difference across a 20-mm-thick sheet of the material is T1 - T2 = 10° C.
(a) What is the heat flux through a 2 m × 2 m sheet of the insulation?
(b) What is the rate of heat transfer through the sheet of insulation?