Consider a large plane wall of thickness L =0.8ft and thermal conductivity k = 1.2 Btu/h ·...

Consider a large plane wall of thickness L =0.8ft and thermal conductivity k = 1.2 Btu/h · ft · °F. The wall is covered with a material that has an emissivity of ε = 0.80 and a solar absorptivity of a = 0.60. The inner surface of the wall is maintained at T1= 520R at all times, while the outer surface is exposed to solar radiation that is incident at a rate of qsolar = 300 Btu/h · ft2. The outer surface is also losing heat by radiation to deep space at 0 K. Determine the temperature of the outer surface of the wall and the rate of heat transfer  through the wall when steady operating conditions are reached. Answers: 554 R, 50.9 Btu/h.ft2