1. Calculate the rate of heat conduction through house walls that are 11.0 cm thick and that have an average thermal conductivity twice that of glass wool. Assume there are no windows or doors. The surface area of the walls is 104m²and their inside surface is at 18.0C , while their outside surface is at 5.00C .

Answer in Watts

2. At what net rate does heat radiate from a 326-m² black roof on a night when the roof's temperature is 30.0C and the surrounding temperature is 15.0C ? The emissivity of the roof is 0.900.

Answer in W