A wood stove is used to heat a single room. The stove is cylindrical in shape, with a diameter of D = 0.400 m and a length of L=0.500 m, and operates at a temperature of T, = 200 °C. (a) If the temperature of the room is T, = 20°C, determine the amount of radiant energy delivered to the room by the stove each second if the emissivity of the stove is e = 0.920.

The surface of a 0.5-m diameter space probe dissipates 150 W of heat to the outside. If the probe surface emits 80% of the heat that comes from the electronic equipment inside of it and the probe does not receive radiation from other surfaces, compute for the surface emissive power in : m²°

A thin outer border of a building's area covers 10×10m^2. The sky temperature is 300K meanwhile the temperature of the sun is 5800K. The overall distance between the sun and earth is 1.5×10^11 meters and the overall sun diameter is 1.4×10^9 meter and the earth diameter is 1.3×10^7 meters. The properties of the outer border are: ελ = 0.5 for λ > 6 µm & ελ = 0.1 for λ < 6 µm. The outer border can be considered a diffuse surface. Air current flows over the border with a velocity of 10 meters/second with a temperature of 300K. Beneath the border, the air inside the building flows over the bottom side of the border at 1 meter/second. Determine the steady-state temperature of the border for these conditions. Please state your assumptions

A particular furnace is shaped like a section of a cone. The top surface of the furnace is uniformly heated by a resistance heater. During operation, the top surface is measured to be 800 K and the power supplied to the resistance heater is 1750 W/m². The sidewall of the furnace is perfectly insulated with & = 0.2. If the emissivity of the top and bottom surfaces are ε = 0.5 and ε = 0.7, respectively, determine the temperatures of the sidewall and the bottom surface of the furnace. A₁ A2 A3 →→D₂ = 20 mm D₁ = 40 mm L = 50 mm