A plate having 10 cm2 area each side is hanging in the middle of a room of 100 m2 total surface area. The plate temperature and emissivity are respectively 800 K and 0.6. The temperature and emissivity value for the surfaces of the room are 300 K and 0.3 respectively. Boltzmann's constant = 5.67 10-8 W/m2K4. The total heat loss from the two surfaces of the plate is

A plate having 10 cm2 area each side is hanging in the middle of a roo

1.	A plate having 10 cm2 area each side is hanging in the middle of a room of 100 m2 total surface area. The plate temperature and emissivity are respectively 800 K and 0.6. The temperature and emissivity value for the surfaces of the room are 300 K and 0.3 respectively. Boltzmann's constant = 5.67 10-8 W/m2K4. The total heat loss from the two surfaces of the plate is
A.	13.66 W
B.	27.32 W
C.	27.87 W
D.	13.66 MW
Answer» C. 27.87 W

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