4. A cubical room 2 m by 2 m by 2 m is heated through the floor by maintaining it at a uniform temperature T1= 250 K, while walls and the ceiling are at 200 K. Assume that the floor has an emissivity 0.9 and the walls and the ceiling have emissivity of 0.6. Determine the rate of heat loss from the floor. Ans: 420.3 W
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We can use the Stefan-Boltzmann law for this: Q_net = A * ε * σ * (T_f^4 - T_s^4) where Q_net is the net radiation heat transfer, A is the surface area of the floor, ε is the emissivity of the floor, σ is the Stefan-Boltzmann constant, T_f is the temperature of Show more…
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