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A small cubical furnace 50 by 50 by 50 cm on the inside is constructed of fireclay brick [k = 1.04 W/m. degree C] with a wall thickness of 10 cm. The inside of the furnace is maintained at 500 degree C, and the outside is maintained at 50 degree C. Calculate the heat lost through the walls.

User Archsx
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1 Answer

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Answer:

Q=1170J/s = 279.516cal/s

Step-by-step explanation:

q=-k.(T₀-T₁)/(x₀- x₁)

q= heat flow density

T= temperature

x= thickness

q= -(1.04 W/m. ºC) . (50ºC-500ºC)/(0.1m-0m)

q=4680W/m²=4,68KW/m²

1KW=1000J/s

∴ q= 4680 J/s.m²

q= Q/A

Q=heat fluw

A= surface= 6 . (0.5m . 0.5m)= 0.25m²

Q= (4680J/s.m²) . (0.25m²)

Q=1170J/s = 279.516cal/s

1J=0.2389cal

User Daboross
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