A large plane wall, 40 cm thick and 8 m2 area, is heated from one side and temperature distribution at a certain time instant is approximately prescribed by the relationT = 80 – 60 x +12 x2 + 25 x3 – 20 x4Where temperature t is in degree Celsius and the distance x in meters. Make calculations for heat energy stored in the wall in unit time.For wall material:Thermal conductivity = 6 W/m K and thermal diffusivity = 0.02 m2/hr.

A large plane wall, 40 cm thick and 8 m2 area, is heated from one sid

1.	A large plane wall, 40 cm thick and 8 m2 area, is heated from one side and temperature distribution at a certain time instant is approximately prescribed by the relationT = 80 – 60 x +12 x2 + 25 x3 – 20 x4Where temperature t is in degree Celsius and the distance x in meters. Make calculations for heat energy stored in the wall in unit time.For wall material:Thermal conductivity = 6 W/m K and thermal diffusivity = 0.02 m2/hr.
A.	870.4 W
B.	345.6 W
C.	791.04 W
D.	238.5 W
Answer» D. 238.5 W

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